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Right answer is (C) GWT

For explanation: GWT, the Google Web TOOLKIT defines a web application API in Java and provides a COMPILER to translate your Java programs into compatible client-side JavaScript whereas Google CLOSURE Tools is a set of tools to help developers build rich web applications with JavaScript.

Correct option is (c) Closure

The explanation is: The Closure LIBRARY is the client-side library that Google uses for Gmail, Google Docs, and other web APPLICATIONS. This library is INTENDED to be USED with the Closure compiler, which strips out unused library functions.

Correct choice is (a) YUI1 and YUI2

The best I can explain: YUI STANDS for yahoo user interface. Like Dojo, it is a LARGE, all-encompassing library with language utilities, DOM utilities, UI widgets, and so on. There are actually two incompatible VERSIONS of YUI, known as YUI 2 and YUI 3.

The correct CHOICE is (a) Facilitates DOM utilities and UI Widgets

Explanation: Like Dojo, it is a large, all-encompassing library with language utilities, DOM utilities, UI widgets, and so on. There are ACTUALLY two INCOMPATIBLE versions of YUI, known as YUI 2 and YUI 3.

Right choice is (b) Advertises incredible DEPTH

To elaborate: The Dojo toolkit is an open-source modular toolkit containing a JavaScript library that is designed for rapidly creating JavaScript/Ajax-based websites and cross-platform applications. Dojo is a large FRAMEWORK that advertises its “incredible depth.” It INCLUDES an extensive set of UI widgets, a package system, a data abstraction LAYER, and more.

Correct choice is (b) YUI

Explanation: YUI is the in-house library of Yahoo!, and it is used on their HOME page. The Yahoo User Interface Library is a discontinued open-source JavaScript library for building RICHLY INTERACTIVE web applications using TECHNIQUES such as Ajax, DHTML, and DOM SCRIPTING.

Correct option is (d) Both jQuery and PROTOTYPE

Easiest explanation: DOM stands for data object MODULATION. The Prototype library focuses on DOM and Ajax utilities like jQuery does, and adds quite a few core-language utilities as well.

Correct option is (b) Framework

Best EXPLANATION: Many WEB developers find it USEFUL to build their web applications on top of a client side framework library. These libraries are “frameworks” in the sense that they build a new higher-level API for client-side programming on top of the standard and proprietary APIs offered by web browsers: once you adopt a framework, your code NEEDS to be written to use the APIs defined by that framework.

Correct choice is (c) Position

To EXPLAIN I would SAY: There is no OBJECT called Position. Whereas elements, location and WINDOW are a predefined object in JavaScript.

Correct ANSWER is (b) timestamp.onclick = function() { this.innerHTML = new Date().toString(); }

The best I can explain: onclick() function is used to handle events when the user clicks on the mouse. The above CODE snippet updates the content of the timestamp ELEMENT when the user clicks on it.

The correct option is (b) Nested FUNCTIONS

The EXPLANATION is: Nested functions are those functions in which one function is defined INSIDE ANOTHER function. Nested functions are common in client-side JavaScript, because of its extensive use of event HANDLERS.

The correct choice is (a) ONLOAD

The best explanation: One of the most IMPORTANT EVENT handlers is the onload handler of the Window object. It is TRIGGERED when the content of the document displayed in the window is stable and ready to be manipulated. JavaScript code is commonly wrapped within an onload event handler.

Correct option is (B) style and className

To explain I would SAY: Each Element object has style and className properties that allow scripts to specify CSS styles for a document element or to alter the CSS CLASS names that apply to the element. firstChild returns the FIRST child node as an element node, a text node or a comment node (depending on which ONE’s first).

Right ANSWER is (a) Element

Easiest explanation: Each Element object has style and className PROPERTIES that allow scripts to specify CSS STYLES for a DOCUMENT element or to alter the CSS class names that APPLY to the element.

Correct answer is (d) timestamp.firstChild

The EXPLANATION is: The first child of a node can be accessed USING the firstChild property. firstChild RETURNS the first child node as an element node, a TEXT node or a comment node (depending on which ONE’s first).

Right answer is (a) DOCUMENT

The BEST I can explain: One of the most important properties of the Window OBJECT is document: it refers to a Document object that represents the CONTENT DISPLAYED in the window.

Correct answer is (b) Register a FUNCTION to be INVOKED after a certain time

Easy explanation: The SETTIMEOUT(), which registers a function to be invoked after a specified amount of time. The setTimeout() method CALLS a function or evaluates an EXPRESSION after a specified number of milliseconds.

Correct OPTION is (C) Window

Explanation: In client-side JavaScript, the Window object is also the GLOBAL object. This means that the Window object is at the top of the scope chain and that its properties and methods are effectively global VARIABLES and global functions.

Right option is (a) ALERT()

Explanation: The Window object defines METHODS like alert(), which DISPLAYS a MESSAGE in a dialog box. A prompt message can be displayed on the screen USING alert().

The correct answer is (B) WINDOW

For explanation I WOULD say: The window object represents a WEB browser window or frame, and you can refer to it with the identifier window. Global variables are properties of the window object and Global functions are methods of the window object.

Correct option is (C) Window

To explain: The Window object is the main entry POINT to all client-side JAVASCRIPT FEATURES and APIs. It represents a web browser window or frame, and you can refer to it with the identifier window.

Correct answer is (c) window.onload = displayTime;

The explanation: window.onload is USED to ACCESS the SCREEN while the PAGE is loading. The above code starts displaying the time when the DOCUMENT loads.

Right option is (b) Retrives from the browser cache

Explanation: If a file of JavaScript code is shared by more than one page, it only needs to be DOWNLOADED once, by the first page that uses it—subsequent PAGES can RETRIEVE it from the browser cache. This MAKES the LOADING process easier and hence faster.

The CORRECT choice is (B) Static Information

To explain I would say: Some pages present static information and can be called DOCUMENTS. The document is a keyword which is used in selecting any PARTICULAR ELEMENT in the document.

Right OPTION is (d) It simplifies the HTML files

Explanation: The main advantage of using the src ATTRIBUTE is that it simplifies your HTML files by allowing you to remove LARGE blocks of JavaScript code from them. HENCE separate files for css and javascript files are made to make the code modular and readable.

Correct answer is (b) var now = new Date();

To explain I would SAY: Date() is a predefined FUNCTION in JAVASCRIPT which returns the date in string form. The above CODE determines the current TIME and stores it in the variable “now”.

The correct ANSWER is (a) HTML

For explanation I would SAY: The “html” TAG is the root element of any HTML document regardless of it containing a JavaScript CODE or not. Body tag includes the main CONTENT that is shown on the website.

Correct option is (a) Between the “SCRIPT” TAG

To elaborate: JavaScript code can appear inline within an HTML file between the “script” tags. Javascript can also be included from an external file SPECIFIED by the src ATTRIBUTE of a “script” tag.

Right choice is (C) getItem()

EASY explanation: To retrieve a value, pass the NAME to getItem(). The getItem() method of the Storage INTERFACE, when passed a key name, will RETURN that key’s value, or null if the key does not exist, in the given Storage object.

The CORRECT ANSWER is (b) External file SPECIFIED by the src attribute of a “script” tag

For explanation: The Client-side JavaScript code is EMBEDDED within HTML documents in four WAYS :

Inline, between a pair of “script” tags

From an external file specified by the src attribute of a “script” tag

In an HTML event handler attribute, such as onclick or onmouseover

In a URL that uses the special javascript: protocol.

Correct ANSWER is (a) Permanent

Easiest explanation: DATA stored through localStorage is permanent. it does not expire and remains stored on the user’s computer until a web APP deletes it or the user asks the browser (through some browser-specific UI) to DELETE it. This data is stored on the client side server and is USED for faster access of data.

The correct option is (c) Both LIFETIME and Scope

Easy explanation: The DIFFERENCE between localStorage and sessionStorage has to do with lifetime and scope: how long the data is SAVED for and who the data is accessible to. SESSION storage is destroyed once the user closes the browser whereas, Local storage stores data with no expiration date.

Correct choice is (a) WINDOW object

For EXPLANATION: Browsers that implement the “Web Storage” draft specification define two properties on the Window object: localStorage and SESSIONSTORAGE. Local storage and Session storage are the web storage objects. Session storage is destroyed once the user CLOSES the browser whereas, Local storage stores data with no expiration date.

Correct option is (C) Web databases

To elaborate: Developers who NEED to work with REALLY huge amounts of data like to use databases, and the most recent browsers have started to integrate CLIENT-side database functionality into their browsers. Client data base helps in making the website FASTER and handling the data easier.

Correct answer is (b) FILE

Easy explanation: These objects can be obtained from the FILESYSTEM property on any file system ENTRY. Some browsers offer additional APIs to create and MANAGE file systems, such as CHROME’s requestFileSystem() method.

The correct OPTION is (a) IE USER Data

The explanation is: Microsoft implements its own PROPRIETARY client-side storage MECHANISM, known as “userData,” in IE5 and later. userData enables the storage of medium amounts of string data and can be used as an alternative to Web Storage in versions of IE before IE8. This makes LOADING of programs and software faster.

The correct answer is (c) Offline WEB Applications

To elaborate: HTML5 DEFINES an “Offline Web Applications” API that allows the caching of web pages and their ASSOCIATED resources (scripts, CSS files, images, and so on). This is client-side storage for web applications themselves rather than just their data, and it allows web apps to install themselves so that they are available even when there is no CONNECTION to the INTERNET.

Right answer is (d) ONLINE Web Applications

To explain: Client-side storage ALLOWS the creater to STORE data on the users system for faster loading of the website. The various FORMS of client-side storage are web databases, filesystem API, OFFLINE web applications and cookies.

Right choice is (c) process

Easiest explanation: The process object is a global that PROVIDES information about, and control over, the current Node.js process. Node DEFINES other important GLOBALS under the process NAMESPACE.

Correct choice is (d) clearTimeout()

To explain I would say: Client-side timer functions are used to perform APPLICATIONS based on TIME constraints. Node SUPPORTS the client-side timer functions SET setTimeout(), setInterval(), clearTimeout(), andclearInterval().

Right CHOICE is (a) setTimeout(function() { console.log(“Hello WORLD”); }, 1000);

To explain I would say: SetTimeout function is used to hold the execution of the CODE with the required amount of time. The argument of the setTimeout includes the function which is to be executed FOLLOWED by the time after which the code is to be executed.

The correct ANSWER is (B) console.log(…);

EXPLANATION: Console.log() prints the content in the argument on to the output SCREEN. Node defines console.log() for debugging output like browsers do.