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Ask your database manufacturer: they all provide XML IMPORT and export modules to connect XML applications with databases. In some trivial cases there will be a 1:1 match between field names in the database table and element type names in the XML Schema or DTD, but in most cases some programming will be required to establish the desired match. This can usually be stored as a procedure so that subsequent uses are simply commands or calls with the relevant parameters. In less trivial, but still simple, cases, you could export by writing a report routine that formats the output as an XML document, and you could import by writing an XSLT transformation that FORMATTED the XML DATA as a load file.

Ask your database manufacturer: they all provide XML import and export modules to connect XML applications with databases. In some trivial cases there will be a 1:1 match between field names in the database table and element type names in the XML Schema or DTD, but in most cases some programming will be required to establish the desired match. This can usually be stored as a procedure so that subsequent uses are simply commands or calls with the relevant parameters. In less trivial, but still simple, cases, you could export by writing a report routine that formats the output as an XML document, and you could import by writing an XSLT transformation that formatted the XML data as a load file.

Yes, if the document type you use provides for math, and your users' browsers are capable of rendering it. The mathematics-using community has developed the MathML Recommendation at the W3C, which is a native XML application suitable for embedding in other DTDs and Schemas. It is also possible to make XML fragments from other DTDs, such as ISO 12083 Math, or OpenMath, or one of your own making. Browsers which display math embedded in SGML existed for many years (eg DynaText, Panorama, Multidoc Pro), and mainstream browsers are now rendering MathML. David Carlisle has produced a set of stylesheets for rendering MathML in browsers. It is also possible to use XSLT to CONVERT XML math markup to LATEX for print (PDF) rendering, or to use XSL:FO. Please note that XML is not itself a programming LANGUAGE, so CONCEPTS such as arithmetic and if-statements (if-then-else logic) are not meaningful in XML DOCUMENTS.

Yes, if the document type you use provides for math, and your users' browsers are capable of rendering it. The mathematics-using community has developed the MathML Recommendation at the W3C, which is a native XML application suitable for embedding in other DTDs and Schemas. It is also possible to make XML fragments from other DTDs, such as ISO 12083 Math, or OpenMath, or one of your own making. Browsers which display math embedded in SGML existed for many years (eg DynaText, Panorama, Multidoc Pro), and mainstream browsers are now rendering MathML. David Carlisle has produced a set of stylesheets for rendering MathML in browsers. It is also possible to use XSLT to convert XML math markup to LATEX for print (PDF) rendering, or to use XSL:FO. Please note that XML is not itself a programming language, so concepts such as arithmetic and if-statements (if-then-else logic) are not meaningful in XML documents.

Because XML lets you define your own markup languages, you can make full use of the extended hypertext features of XML (see the question on Links) to store or link to metadata in any format (eg USING ISO 11179, as a Topic Maps Published Subject, with DUBLIN Core, Warwick Framework, or with Resource DESCRIPTION Framework (RDF), or even Platform for Internet Content Selection (PICS)). There are no predefined elements in XML, because it is an architecture, not an application, so it is not part of XML's job to specify how or if authors should or should not implement metadata. You are therefore free to use any suitable method. Browser makers may also have their own architectural recommendations or methods to propose.

Because XML lets you define your own markup languages, you can make full use of the extended hypertext features of XML (see the question on Links) to store or link to metadata in any format (eg using ISO 11179, as a Topic Maps Published Subject, with Dublin Core, Warwick Framework, or with Resource Description Framework (RDF), or even Platform for Internet Content Selection (PICS)). There are no predefined elements in XML, because it is an architecture, not an application, so it is not part of XML's job to specify how or if authors should or should not implement metadata. You are therefore free to use any suitable method. Browser makers may also have their own architectural recommendations or methods to propose.

YES, any programming language can be used to output data from any source in XML format. There is a growing NUMBER of front-ends and back-ends for programming environments and data management environments to automate this. JAVA is just the most popular one at the MOMENT. There is a large BODY of middleware (APIs) written in Java and other languages for managing data either in XML or with XML input or output.

Yes, any programming language can be used to output data from any source in XML format. There is a growing number of front-ends and back-ends for programming environments and data management environments to automate this. Java is just the most popular one at the moment. There is a large body of middleware (APIs) written in Java and other languages for managing data either in XML or with XML input or output.

This will depend on what facilities your users' browsers implement. XML is about describing information; scripting languages and languages for embedded functionality are software which enables the information to be manipulated at the user's end, so these languages do not normally have any place in an XML file itself, but in stylesheets like XSL and CSS where they can be ADDED to generated HTML. XML itself provides a way to define the markup needed to implement scripting languages: as a neutral standard it neither encourages not discourages their use, and does not favour one language over another, so it is possible to use XML markup to store the program code, from where it can be RETRIEVED by (for example) XSLT and re-expressed in a HTML script element. Server-side script embedding, like PHP or ASP, can be used with the relevant server to modify the XML code on the fly, as the document is served, just as they can with HTML. Authors should be aware, however, that embedding server-side scripting MAY mean the file as stored is not valid XML: it only becomes valid when processed and served, so CARE must be TAKEN when using validating editors or other software to handle or manage such files. A better solution may be to use an XML serving solution like Cocoon, AxKit, or PropelX.

This will depend on what facilities your users' browsers implement. XML is about describing information; scripting languages and languages for embedded functionality are software which enables the information to be manipulated at the user's end, so these languages do not normally have any place in an XML file itself, but in stylesheets like XSL and CSS where they can be added to generated HTML. XML itself provides a way to define the markup needed to implement scripting languages: as a neutral standard it neither encourages not discourages their use, and does not favour one language over another, so it is possible to use XML markup to store the program code, from where it can be retrieved by (for example) XSLT and re-expressed in a HTML script element. Server-side script embedding, like PHP or ASP, can be used with the relevant server to modify the XML code on the fly, as the document is served, just as they can with HTML. Authors should be aware, however, that embedding server-side scripting may mean the file as stored is not valid XML: it only becomes valid when processed and served, so care must be taken when using validating editors or other software to handle or manage such files. A better solution may be to use an XML serving solution like Cocoon, AxKit, or PropelX.

XML itself is not a programming language, so XML files don't ‘run' or ‘execute'. XML is a MARKUP specification language and XML files are just data: they sit there until you run a program which DISPLAYS them (like a browser) or does some work with them (like a converter which writes the data in ANOTHER format, or a database which reads the data), or modifies them (like an editor). If you want to view or display an XML file, open it with an XML editor or an question B.3, XML browser. The water is muddied by XSL (both XSLT and XSL:FO) which use XML SYNTAX to implement a declarative programming language. In these cases it is arguable that you can ‘execute' XML code, by running a PROCESSING application like Saxon, which compiles the directives specified in XSLT files into Java bytecode to process XML.

XML itself is not a programming language, so XML files don't ‘run' or ‘execute'. XML is a markup specification language and XML files are just data: they sit there until you run a program which displays them (like a browser) or does some work with them (like a converter which writes the data in another format, or a database which reads the data), or modifies them (like an editor). If you want to view or display an XML file, open it with an XML editor or an question B.3, XML browser. The water is muddied by XSL (both XSLT and XSL:FO) which use XML syntax to implement a declarative programming language. In these cases it is arguable that you can ‘execute' XML code, by running a processing application like Saxon, which compiles the directives specified in XSLT files into Java bytecode to process XML.

In HTML, default styling was built into the browsers because the tagset of HTML was predefined and hardwired into browsers. In XML, where you can define your own tagset, browsers cannot possibly be expected to GUESS or know in advance what names you are going to use and what they will mean, so you need a STYLESHEET if you want to display formatted text. Browsers which read XML will accept and use a CSS stylesheet at a minimum, but you can also use the more POWERFUL XSLT stylesheet language to transform your XML into HTML—which browsers, of course, already know how to display (and that HTML can still use a CSS stylesheet). This way you get all the document management benefits of using XML, but you don't have to worry about your readers needing XML smarts in their browsers.

In HTML, default styling was built into the browsers because the tagset of HTML was predefined and hardwired into browsers. In XML, where you can define your own tagset, browsers cannot possibly be expected to guess or know in advance what names you are going to use and what they will mean, so you need a stylesheet if you want to display formatted text. Browsers which read XML will accept and use a CSS stylesheet at a minimum, but you can also use the more powerful XSLT stylesheet language to transform your XML into HTML—which browsers, of course, already know how to display (and that HTML can still use a CSS stylesheet). This way you get all the document management benefits of using XML, but you don't have to worry about your readers needing XML smarts in their browsers.

Graphics have traditionally just been links which happen to have a picture file at the end rather than another piece of text. They can therefore be implemented in any way supported by the XLink and XPointer specifications including using similar syntax to existing HTML images. They can also be referenced using XML's built-in NOTATION and ENTITY mechanism in a similar way to standard SGML, as external unparsed entities.

However, the SVG specification lets you use XML markup to draw vector graphics objects directly in your XML file. This provides ENORMOUS power for the inclusion of portable graphics, especially interactive or animated sequences, and it is now slowly becoming supported in BROWSERS.

The XML linking specifications for external images give you much better control over the traversal and activation of links, so an author can specify, for example, whether or not to have an image appear when the page is loaded, or on a click from the user, or in a separate window, without having to resort to scripting.

XML itself doesn't predicate or restrict graphic file formats: GIF, JPG, TIFF, PNG, CGM, EPS, and SVG at a minimum would seem to make sense; however, vector formats (EPS, SVG) are normally essential for non-photographic images (diagrams).

You cannot embed a raw binary graphics file (or any other binary [non-text] data) directly into an XML file because any bytes happening to resemble markup would get misinterpreted: you must refer to it by linking (see below). It is, however, possible to include a text-encoded transformation of a binary file as a CDATA Marked Section, using something like UUencode with the markup characters ], & and > removed from the map so that they could not occur as an erroneous CDATA termination sequence and be misinterpreted. You could even use simple hexadecimal ENCODING as used in PostScript. For vector graphics, however, the solution is to use SVG .

Sound files are binary objects in the same way that external graphics are, so they can only be referenced externally. Music files written in MusiXML or an XML variant of SMDL could however be EMBEDDED in the same way as for SVG.

The point about using entities to manage your graphics is that you can keep the list of entity declarations separate from the rest of the document, so you can re-use the names if an image is needed more than once, but only store the physical file specification in a single place. This is available only when using a DTD, not a Schema.

Graphics have traditionally just been links which happen to have a picture file at the end rather than another piece of text. They can therefore be implemented in any way supported by the XLink and XPointer specifications including using similar syntax to existing HTML images. They can also be referenced using XML's built-in NOTATION and ENTITY mechanism in a similar way to standard SGML, as external unparsed entities.

However, the SVG specification lets you use XML markup to draw vector graphics objects directly in your XML file. This provides enormous power for the inclusion of portable graphics, especially interactive or animated sequences, and it is now slowly becoming supported in browsers.

The XML linking specifications for external images give you much better control over the traversal and activation of links, so an author can specify, for example, whether or not to have an image appear when the page is loaded, or on a click from the user, or in a separate window, without having to resort to scripting.

XML itself doesn't predicate or restrict graphic file formats: GIF, JPG, TIFF, PNG, CGM, EPS, and SVG at a minimum would seem to make sense; however, vector formats (EPS, SVG) are normally essential for non-photographic images (diagrams).

You cannot embed a raw binary graphics file (or any other binary [non-text] data) directly into an XML file because any bytes happening to resemble markup would get misinterpreted: you must refer to it by linking (see below). It is, however, possible to include a text-encoded transformation of a binary file as a CDATA Marked Section, using something like UUencode with the markup characters ], & and > removed from the map so that they could not occur as an erroneous CDATA termination sequence and be misinterpreted. You could even use simple hexadecimal encoding as used in PostScript. For vector graphics, however, the solution is to use SVG .

Sound files are binary objects in the same way that external graphics are, so they can only be referenced externally. Music files written in MusiXML or an XML variant of SMDL could however be embedded in the same way as for SVG.

The point about using entities to manage your graphics is that you can keep the list of entity declarations separate from the rest of the document, so you can re-use the names if an image is needed more than once, but only store the physical file specification in a single place. This is available only when using a DTD, not a Schema.

You can't: XML isn't a programming language, so you can't say things LIKE 
<google if {DB}="A">bar</google> 

If you need to make an element optional, based on some internal or external criteria, you can do so in a Schema. DTDs have no internal referential mechanism, so it isn't possible to express this KIND of conditionality in a DTD at the individual element level. 

It is possible to express PRESENCE-or-absence conditionality in a DTD for the whole document, by USING parameter entities as switches to include or ignore certain sections of the DTD based on settings either hardwired in the DTD or supplied in the internal subset. Both the TEI and Docbook DTDs use this mechanism to implement modularity. 

Alternatively you can make the element entirely optional in the DTD or Schema, and provide code in your processing software that checks for its presence or absence. This defers the checking until the processing stage: one of the reasons for Schemas is to provide this kind of checking at the time of document creation or editing.

I have to do an overview of XML for my manager/client/investor/advisor. 

You can't: XML isn't a programming language, so you can't say things like 
<google if {DB}="A">bar</google> 

If you need to make an element optional, based on some internal or external criteria, you can do so in a Schema. DTDs have no internal referential mechanism, so it isn't possible to express this kind of conditionality in a DTD at the individual element level. 

It is possible to express presence-or-absence conditionality in a DTD for the whole document, by using parameter entities as switches to include or ignore certain sections of the DTD based on settings either hardwired in the DTD or supplied in the internal subset. Both the TEI and Docbook DTDs use this mechanism to implement modularity. 

Alternatively you can make the element entirely optional in the DTD or Schema, and provide code in your processing software that checks for its presence or absence. This defers the checking until the processing stage: one of the reasons for Schemas is to provide this kind of checking at the time of document creation or editing.

I have to do an overview of XML for my manager/client/investor/advisor. 

One solution is to simply rename one of the Address element types -- for example, we could rename the second element type IPADDRESS. However, this is not a useful long term solution. One of the hopes of XML is that people will standardize XML languages for various SUBJECT areas and write modular code to process those languages. By reusing existing languages and code, people can quickly define new languages and write applications that process them. If we rename the second Address element type to IPAddress, we will break any code that expects the old name. A better answer is to assign each language (including its Address element type) to a different NAMESPACE. This allows us to continue using the Address name in each language, but to distinguish between the two different element types. The mechanism by which we do this is XML NAMESPACES. NOTE that by assigning each Address name to an XML namespace, we actually change the name to a two-part name consisting of the name of the XML namespace plus the name Address. This means that any code that recognizes just the name Address will need to be changed to recognize the new two-part name. However, this only needs to be done once, as the two-part name is universally unique.

One solution is to simply rename one of the Address element types -- for example, we could rename the second element type IPAddress. However, this is not a useful long term solution. One of the hopes of XML is that people will standardize XML languages for various subject areas and write modular code to process those languages. By reusing existing languages and code, people can quickly define new languages and write applications that process them. If we rename the second Address element type to IPAddress, we will break any code that expects the old name. A better answer is to assign each language (including its Address element type) to a different namespace. This allows us to continue using the Address name in each language, but to distinguish between the two different element types. The mechanism by which we do this is XML namespaces. Note that by assigning each Address name to an XML namespace, we actually change the name to a two-part name consisting of the name of the XML namespace plus the name Address. This means that any code that recognizes just the name Address will need to be changed to recognize the new two-part name. However, this only needs to be done once, as the two-part name is universally unique.

No. 
If an element type or attribute name is not specifically declared to be in an XML namespace -- that is, it is unprefixed and (in the case of element type NAMES) there is no DEFAULT XML namespace -- then that name is not in any XML namespace. If you want, you can think of it as having a null URI as its name, ALTHOUGH no "null" XML namespace actually exists. For example, in the following, the element type name B and the attribute names C and E are not in any XML namespace: 
<google:A xmlns:google="HTTP://www.google.org/"&GT;
<B C="bar"/>
<google:D E="bar"/>
</google:A>

No. 
If an element type or attribute name is not specifically declared to be in an XML namespace -- that is, it is unprefixed and (in the case of element type names) there is no default XML namespace -- then that name is not in any XML namespace. If you want, you can think of it as having a null URI as its name, although no "null" XML namespace actually exists. For example, in the following, the element type name B and the attribute names C and E are not in any XML namespace: 
<google:A xmlns:google="http://www.google.org/">
<B C="bar"/>
<google:D E="bar"/>
</google:A>

No.
XML namespaces apply only to element type and attribute names. Furthermore, in an XML documentthat CONFORMS to the XML namespaces recommendation, entity names, notation names, and PROCESSING instruction targets must not contain COLONS.

No.
XML namespaces apply only to element type and attribute names. Furthermore, in an XML documentthat conforms to the XML namespaces recommendation, entity names, notation names, and processing instruction targets must not contain colons.

Anybody can CREATE an XML namespace -- all you need to do is assign a URI as its name and decide what element type and attribute NAMES are in it. The URI must be under your control and should not be being used to IDENTIFY a DIFFERENT XML namespace, such as by a COWORKER.

Anybody can create an XML namespace -- all you need to do is assign a URI as its name and decide what element type and attribute names are in it. The URI must be under your control and should not be being used to identify a different XML namespace, such as by a coworker.

There is no required CONFIGURATION for the XPointer Framework. The uberjar COMMAND line utility provides some configuration OPTIONS. Applications configure individual XPointer PROCESSORS when they obtain an instance from an appropriate XPointerProcessor factory method.

There is no required configuration for the XPointer Framework. The uberjar command line utility provides some configuration options. Applications configure individual XPointer processors when they obtain an instance from an appropriate XPointerProcessor factory method.

Yes, provided you use up-to-date SGML software which knows about the WebSGML Adaptations TC to ISO 8879 (the features needed to support XML, such as the variant form for EMPTY elements; some aspects of the SGML Declaration such as NAMECASE GENERAL NO; multiple attribute token list declarations, etc).

An alternative is to use an SGML DTD to let you create a fully-normalised SGML file, but one which does not use empty elements; and then remove the DocType Declaration so it BECOMES a well-formed DTDless XML file. Most SGML tools now handle XML files well, and provide an option SWITCH between the two standards.

Yes, provided you use up-to-date SGML software which knows about the WebSGML Adaptations TC to ISO 8879 (the features needed to support XML, such as the variant form for EMPTY elements; some aspects of the SGML Declaration such as NAMECASE GENERAL NO; multiple attribute token list declarations, etc).

An alternative is to use an SGML DTD to let you create a fully-normalised SGML file, but one which does not use empty elements; and then remove the DocType Declaration so it becomes a well-formed DTDless XML file. Most SGML tools now handle XML files well, and provide an option switch between the two standards.

Yes, the W3C recommends USING XHTML which is ‘a reformulation of HTML 4 in XML 1.0’. This specification defines HTML as an XML APPLICATION, and provides three DTDs corresponding to the ones defined by HTML 4.* (Strict, Transitional, and Frameset).

The SEMANTICS of the elements and their attributes are as defined in the W3C Recommendation for HTML 4. These semantics provide the foundation for future extensibility of XHTML. Compatibility with EXISTING HTML browsers is possible by FOLLOWING a small set of guidelines

Yes, the W3C recommends using XHTML which is ‘a reformulation of HTML 4 in XML 1.0’. This specification defines HTML as an XML application, and provides three DTDs corresponding to the ones defined by HTML 4.* (Strict, Transitional, and Frameset).

The semantics of the elements and their attributes are as defined in the W3C Recommendation for HTML 4. These semantics provide the foundation for future extensibility of XHTML. Compatibility with existing HTML browsers is possible by following a small set of guidelines

No, although it's USEFUL because a lot of XML terminology and practice derives from two decades'experience of SGML. Be aware that ‘knowing HTML’ is not the same as ‘UNDERSTANDING SGML’. Although HTML was WRITTEN as an SGML application, browsers ignore most of it (which is why so MANY useful THINGS don't work), so just because something is done a certain way in HTML browsers does not mean it's correct, least of all in XML.

No, although it's useful because a lot of XML terminology and practice derives from two decades'experience of SGML. Be aware that ‘knowing HTML’ is not the same as ‘understanding SGML’. Although HTML was written as an SGML application, browsers ignore most of it (which is why so many useful things don't work), so just because something is done a certain way in HTML browsers does not mean it's correct, least of all in XML.

No. XML itself does not replace HTML. Instead, it provides an alternative which ALLOWS you to DEFINE your own set of markup elements. HTML is expected to remain in common use for some TIME to come, and the CURRENT version of HTML is in XML syntax. XML is designed to make the writing of DTDs much simpler than with full SGML.

No. XML itself does not replace HTML. Instead, it provides an alternative which allows you to define your own set of markup elements. HTML is expected to remain in common use for some time to come, and the current version of HTML is in XML syntax. XML is designed to make the writing of DTDs much simpler than with full SGML.

The way candidates answer this question may provide insight into their VIEW of XML data. For those who view XML primarily as a way to denote structure for text files, a common answer is to build a full-text search and handle the data similarly to the way Internet PORTALS handle HTML pages. Others CONSIDER XML as a standard way of transferring structured data between disparate systems. These candidates often describe some scheme of importing XML into a relational or object database and relying on the database's engine for searching. Lastly, candidates that have WORKED with vendors specializing in this area often say that the best way the handle this situation is to use a third party SOFTWARE package optimized for XML data.

The way candidates answer this question may provide insight into their view of XML data. For those who view XML primarily as a way to denote structure for text files, a common answer is to build a full-text search and handle the data similarly to the way Internet portals handle HTML pages. Others consider XML as a standard way of transferring structured data between disparate systems. These candidates often describe some scheme of importing XML into a relational or object database and relying on the database's engine for searching. Lastly, candidates that have worked with vendors specializing in this area often say that the best way the handle this situation is to use a third party software package optimized for XML data.

Every interview session should have at LEAST one trick QUESTION. Although possible when using SGML, XML DTDs don't support defining external entity references in ATTRIBUTE values. It's more important for the candidate to respond to this question in a logical way than the candidate know the some what obscure ANSWER.

Every interview session should have at least one trick question. Although possible when using SGML, XML DTDs don't support defining external entity references in attribute values. It's more important for the candidate to respond to this question in a logical way than the candidate know the some what obscure answer.

Successful CANDIDATES should recognize this as one of the most basic applications of XSLT. If they are not able to construct a REPLY similar to the example below, they should at least be able to identify the components necessary for this operation: XSL:template to match the APPROPRIATE XML element, xsl:value-of to select the attribute value, and the optional xsl:apply-templates to continue processing the document.
Extract Attributes from XML DATA
Example 1.
<xsl:template match="element-name">
Attribute Value:
<xsl:value-of select="@attribute"/>
<xsl:apply-templates/>
</xsl:template>

Successful candidates should recognize this as one of the most basic applications of XSLT. If they are not able to construct a reply similar to the example below, they should at least be able to identify the components necessary for this operation: xsl:template to match the appropriate XML element, xsl:value-of to select the attribute value, and the optional xsl:apply-templates to continue processing the document.
Extract Attributes from XML Data
Example 1.
<xsl:template match="element-name">
Attribute Value:
<xsl:value-of select="@attribute"/>
<xsl:apply-templates/>
</xsl:template>

Although XML does not require data to be validated against a DTD, many of the benefits of using the technology are derived from being able to VALIDATE XML documents against business or TECHNICAL architecture rules. Polling for the list of DTDs that developers have worked with provides INSIGHT to their general exposure to the technology. The ideal candidate will have knowledge of several of the COMMONLY used DTDs such as FpML, DocBook, HRML, and RDF, as well as experience designing a custom DTD for a particular project where no standard existed.

Although XML does not require data to be validated against a DTD, many of the benefits of using the technology are derived from being able to validate XML documents against business or technical architecture rules. Polling for the list of DTDs that developers have worked with provides insight to their general exposure to the technology. The ideal candidate will have knowledge of several of the commonly used DTDs such as FpML, DocBook, HRML, and RDF, as well as experience designing a custom DTD for a particular project where no standard existed.

Superficially, this is a fairly BASIC question. However, the point is not to determine whether CANDIDATES understand the CONCEPT of a parser but rather have them WALK through the process of parsing XML documents step-by-step. Determining whether a non-validating or validating parser is needed, choosing the appropriate parser, and handling errors are all IMPORTANT aspects to this process that should be included in the candidate's response.

Superficially, this is a fairly basic question. However, the point is not to determine whether candidates understand the concept of a parser but rather have them walk through the process of parsing XML documents step-by-step. Determining whether a non-validating or validating parser is needed, choosing the appropriate parser, and handling errors are all important aspects to this process that should be included in the candidate's response.

Here are a few reasons for using XML .
* XML can be used to describe and identify INFORMATION accurately and unambiguously, in a way that computers can be programmed to ‘understand’ (well, at least manipulate as if they could understand).
* XML allows documents which are all the same type to be created consistently and without structural errors, because it provides a standardised way of describing, controlling, or allowing/disallowing particular types of document structure. [Note that this has absolutely nothing whatever to do with formatting, appearance, or the actual text content of your documents, only the structure of them].
* XML provides a robust and durable format for information storage and transmission. Robust because it is based on a proven standard, and can thus be tested and verified; durable because it uses plain-text file formats which will outlast proprietary BINARY ones.
* XML provides a common syntax for messaging systems for the exchange of information between APPLICATIONS. Previously, each messaging system had its own format and all were different, which made inter-system messaging unnecessarily messy, complex, and expensive. If everyone uses the same syntax it makes WRITING these systems much faster and more reliable.
* XML is free. Not just free of charge (free as in beer) but free of legal encumbrances (free as in speech). It doesn't belong to anyone, so it can't be hijacked or pirated. And you don't have to pay a fee to use it (you can of course choose to use COMMERCIAL software to deal with it, for lots of good reasons, but you don't pay for XML itself).
* XML information can be manipulated programmatically (under machine control), so XML documents can be pieced together from disparate sources, or taken apart and re-used in different ways. They can be converted into almost any other format with no loss of information.
* XML lets you separate form from content. Your XML file contains your document information (text, data) and identifies its structure: your formatting and other processing needs are identified separately in a stylesheet or processing system. The two are combined at output time to apply the required formatting to the text or data identified by its structure (location, position, rank, order, or whatever).

Here are a few reasons for using XML .
* XML can be used to describe and identify information accurately and unambiguously, in a way that computers can be programmed to ‘understand’ (well, at least manipulate as if they could understand).
* XML allows documents which are all the same type to be created consistently and without structural errors, because it provides a standardised way of describing, controlling, or allowing/disallowing particular types of document structure. [Note that this has absolutely nothing whatever to do with formatting, appearance, or the actual text content of your documents, only the structure of them].
* XML provides a robust and durable format for information storage and transmission. Robust because it is based on a proven standard, and can thus be tested and verified; durable because it uses plain-text file formats which will outlast proprietary binary ones.
* XML provides a common syntax for messaging systems for the exchange of information between applications. Previously, each messaging system had its own format and all were different, which made inter-system messaging unnecessarily messy, complex, and expensive. If everyone uses the same syntax it makes writing these systems much faster and more reliable.
* XML is free. Not just free of charge (free as in beer) but free of legal encumbrances (free as in speech). It doesn't belong to anyone, so it can't be hijacked or pirated. And you don't have to pay a fee to use it (you can of course choose to use commercial software to deal with it, for lots of good reasons, but you don't pay for XML itself).
* XML information can be manipulated programmatically (under machine control), so XML documents can be pieced together from disparate sources, or taken apart and re-used in different ways. They can be converted into almost any other format with no loss of information.
* XML lets you separate form from content. Your XML file contains your document information (text, data) and identifies its structure: your formatting and other processing needs are identified separately in a stylesheet or processing system. The two are combined at output time to apply the required formatting to the text or data identified by its structure (location, position, rank, order, or whatever).

HTML was already overburdened with dozens of interesting but incompatible inventions from different manufacturers, because it provides only one way of describing your information.

XML allows groups of people or ORGANIZATIONS to question C.13, create their own customized markup applications for exchanging information in their domain (music, chemistry, electronics, hill-walking, FINANCE, surfing, petroleum geology, linguistics, cooking, knitting, stellar cartography, history, engineering, rabbit-keeping, question C.19, MATHEMATICS, genealogy, etc).

HTML is now well beyond the LIMIT of its usefulness as a way of describing information, and while it will continue to play an important role for the content it currently represents, many new applications require a more robust and flexible INFRASTRUCTURE.

HTML was already overburdened with dozens of interesting but incompatible inventions from different manufacturers, because it provides only one way of describing your information.

XML allows groups of people or organizations to question C.13, create their own customized markup applications for exchanging information in their domain (music, chemistry, electronics, hill-walking, finance, surfing, petroleum geology, linguistics, cooking, knitting, stellar cartography, history, engineering, rabbit-keeping, question C.19, mathematics, genealogy, etc).

HTML is now well beyond the limit of its usefulness as a way of describing information, and while it will continue to play an important role for the content it currently represents, many new applications require a more robust and flexible infrastructure.

The Simple Object Access Protocol (SOAP) uses XML to define a protocol for the exchange of information in DISTRIBUTED computing environments. SOAP consists of three components: an envelope, a set of encoding rules, and a convention for representing REMOTE procedure calls. Unless experience with SOAP is a direct REQUIREMENT for the open position, knowing the specifics of the protocol, or how it can be used in conjunction with HTTP, is not as important as identifying it as a natural APPLICATION of XML

The Simple Object Access Protocol (SOAP) uses XML to define a protocol for the exchange of information in distributed computing environments. SOAP consists of three components: an envelope, a set of encoding rules, and a convention for representing remote procedure calls. Unless experience with SOAP is a direct requirement for the open position, knowing the specifics of the protocol, or how it can be used in conjunction with HTTP, is not as important as identifying it as a natural application of XML

There are literally thousands of applications that can benefit from XML technologies. The point of this question is not to have the candidate rattle off a LAUNDRY list of projects that they have worked on, but, rather, to allow the candidate to explain the rationale for choosing XML by citing a few real world examples. For instance, one appropriate answer is that XML allows CONTENT management systems to store documents independently of their format, which thereby reduces data redundancy. Another answer relates to B2B exchanges or supply chain management systems. In these instances, XML PROVIDES a mechanism for multiple companies to exchange data according to an agreed UPON set of rules. A third common response involves wireless applications that require WML to render data on hand held devices.

There are literally thousands of applications that can benefit from XML technologies. The point of this question is not to have the candidate rattle off a laundry list of projects that they have worked on, but, rather, to allow the candidate to explain the rationale for choosing XML by citing a few real world examples. For instance, one appropriate answer is that XML allows content management systems to store documents independently of their format, which thereby reduces data redundancy. Another answer relates to B2B exchanges or supply chain management systems. In these instances, XML provides a mechanism for multiple companies to exchange data according to an agreed upon set of rules. A third common response involves wireless applications that require WML to render data on hand held devices.

XML is a project of the World Wide WEB Consortium (W3C), and the development of the specification is supervised by an XML Working Group. A Special Interest Group of co-opted contributors and experts from various fields contributed comments and reviews by email.

XML is a public format: it is not a proprietary development of any COMPANY, although the membership of the WG and the SIG represented COMPANIES as well as research and ACADEMIC institutions. The v1.0 specification was ACCEPTED by the W3C as a Recommendation on Feb 10, 1998.

XML is a project of the World Wide Web Consortium (W3C), and the development of the specification is supervised by an XML Working Group. A Special Interest Group of co-opted contributors and experts from various fields contributed comments and reviews by email.

XML is a public format: it is not a proprietary development of any company, although the membership of the WG and the SIG represented companies as well as research and academic institutions. The v1.0 specification was accepted by the W3C as a Recommendation on Feb 10, 1998.

Not quite; SGML is the mother tongue, and has been used for describing thousands of different DOCUMENT types in many fields of HUMAN activity, from transcriptions of ancient Irish manuscripts to the technical documentation for stealth bombers, and from patients' clinical records to musical notation. SGML is very large and complex, however, and probably overkill for most common office desktop APPLICATIONS.

XML is an abbreviated version of SGML, to make it easier to use over the Web, easier for you to define your own document types, and easier for programmers to WRITE programs to handle them. It omits all the complex and less-used options of SGML in return for the benefits of being easier to write applications for, easier to understand, and more suited to delivery and interoperability over the Web. But it is still SGML, and XML files may still be processed in the same way as any other SGML FILE (see the question on XML software).

HTML is just one of many SGML or XML applications—the one most frequently used on the Web. Technical readers may find it more useful to think of XML as being SGML-- rather than HTML++.

Not quite; SGML is the mother tongue, and has been used for describing thousands of different document types in many fields of human activity, from transcriptions of ancient Irish manuscripts to the technical documentation for stealth bombers, and from patients' clinical records to musical notation. SGML is very large and complex, however, and probably overkill for most common office desktop applications.

XML is an abbreviated version of SGML, to make it easier to use over the Web, easier for you to define your own document types, and easier for programmers to write programs to handle them. It omits all the complex and less-used options of SGML in return for the benefits of being easier to write applications for, easier to understand, and more suited to delivery and interoperability over the Web. But it is still SGML, and XML files may still be processed in the same way as any other SGML file (see the question on XML software).

HTML is just one of many SGML or XML applications—the one most frequently used on the Web. Technical readers may find it more useful to think of XML as being SGML-- rather than HTML++.

Even if candidates have never participated in a project INVOLVING this type of architecture, they should recognize it as one of the common uses of XML. Querying a database and then formatting the result set so that it can be validated as an XML document allows developers to translate the data into an HTML table using XSLT rules. Consequently, the FORMAT of the RESULTING HTML table can be modified without CHANGING the database query or application CODE since the document rendering logic is isolated to the XSLT rules.

Even if candidates have never participated in a project involving this type of architecture, they should recognize it as one of the common uses of XML. Querying a database and then formatting the result set so that it can be validated as an XML document allows developers to translate the data into an HTML table using XSLT rules. Consequently, the format of the resulting HTML table can be modified without changing the database query or application code since the document rendering logic is isolated to the XSLT rules.

A markup language is a set of words and symbols for describing the identity of pieces of a document (for example ‘this is a paragraph’, ‘this is a HEADING’, ‘this is a list’, ‘this is the caption of this figure’, ETC). Programs can use this with a STYLE sheet to CREATE output for screen, print, audio, video, Braille, etc.
Some markup LANGUAGES (e.g. those used in word processors) only describe appearances (‘this is italics’, ‘this is bold’), but this method can only be used for display, and is not normally re-usable for anything else.

A markup language is a set of words and symbols for describing the identity of pieces of a document (for example ‘this is a paragraph’, ‘this is a heading’, ‘this is a list’, ‘this is the caption of this figure’, etc). Programs can use this with a style sheet to create output for screen, print, audio, video, Braille, etc.
Some markup languages (e.g. those used in word processors) only describe appearances (‘this is italics’, ‘this is bold’), but this method can only be used for display, and is not normally re-usable for anything else.