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• Write less do more − For a huge code in JavaScript, we require comparatively a very less number of lines of CoffeeScript.
• Easily understandable − The SHORTHAND form of JavaScript is CoffeeScript, its syntax is quite simple as compared to JavaScript. Making use of CoffeeScript, we can document clean, clear, and easily discernible codes.
• Reliable − CoffeeScript is a secure and reliable programming LANGUAGE to create dynamic programs.
• Readable and maintainable − CoffeeScript offers aliases for most of the operators, making the code readable. Also maintaining the programs written in CoffeeScript is effortless.
• Class-based inheritance − JavaScript does not have classes, in place of them, it offers powerful but complicated prototypes. Unlike JavaScript, in CoffeeScript, we can make classes and inherit them. Additionally, it also provides instant and static properties along with mixins. It utilizes JavaScript's native prototype to construct classes.
• No var keyword − There is no requirement to utilize the var keyword to form a variable in CoffeeScript, hence we can evade accidental or undesirable scope deceleration.
• Avoids problematic symbols − There is no requirement to utilize the problematic parenthesis and semicolons in CoffeeScript. In place of curly braces, we can utilize whitespaces to distinguish the block codes such as functions, loops, etc.
• Extensive library support − In CoffeeScript, we can utilize the JavaScript libraries and vice VERSA. Thus, we have ACCESS to a myriad set of libraries while OPERATING with CoffeeScript.

Generally, Data-* attributes of HTML are utilized to accumulate the CUSTOM data, which is private to the web application or PAGE. This custom data is for personalizing the JavaScript of the user as per the user action on the web page.

These days, Data-*attributes are not advised to utilize as the user can change the attribute easily just by utilizing the browser INSPECT console.

Example:

When an HTTP request is sent to the server by the USER, the user browser ALSO sends a chunk of additional information regarding the language preference as the Accept-Language header. Then the server reads the HTTP request with the Accept-Language header and sends the DOCUMENT version BACK along with the right language and declares the language attribute Lang in the HTML tag.

Example:

There are numerous things accountable for lowering page load time. Let us look at the three BEST ways to reduce its loading time:

• Image OPTIMIZATION: It is always advised to scale your videos and pictures before uploading them to a page.
• Browser CACHE: The utilization of cache will boost speed for pages that you have visited already.
• Optimize and compress content: Compressing the content of a website decreases the load time of a page to a GREAT extent.
• StyleSheet Reference on Top: Setting stylesheet reference to the header of a doc ALLOWS your page to load quickly.

While creating a complicated front-end application with TONS of non-code static possessions, for instance, CSS, fonts, images, etc, then, of course, you should make use of Webpack since it has a lot of amazing benefits.

If you have a small application that doesn't have a lot of static RESOURCES and you only have to create one file of JAVASCRIPT to help the customers, then Webpack should be more OVERHEAD than NEEDED.

ClickJacking is a security attack where the user is fooled to click on something while they assume they are clicking another thing. The attack mostly happens by the HTML frames. ClickJacking is also regarded as the user interface redressing. It lets the user think that they are utilising a normal UI in the web page, but in ACTUALITY, there is an unseen UI in control; you can think of it as the user interface being redressed. When users click on one thing, ASSUMING it to be SECURE and safe, the HIDDEN UI executes another action.

An iterative design procedure, User-centred design lets the designers focus on the clients and their needs in every design process PHASE. The user-centered design calls for linking USERS in the design process via a variability of design and research techniques to make usable and highly accessible PRODUCTS. User-centered design demands that designers should utilize a combination of generative (such as brainstorming) and investigative (interviews and surveys) methods and instruments to create an UNDERSTANDING of user requirements.

From most other programming languages, Inheritance in JavaScript is different. JavaScript's OBJECT system is prototype-based, not class-based. OBJECTS in JavaScript are just a set of VALUE pairs and a name (KEY). TALKING about inheritance, JavaScript just has one construct: objects. Each object has a private property that includes a link to another object named its prototype.

CSS splits the page into grids and UTILIZES those grids to HANDLE the HTML content. Utilizing the Grids, CSS can stack and highlight various ELEMENTS in different PARTS of the grids.

The primary responsibility of the rendering engine is to highlight the requested PAGE on the browser’s screen. Rendering engines can show XML and HTML images and documents. If you’re utilising additional plugins, the engines can also exhibit various documents like PDF.

• Receives the requested document: The contents of the requested document is obtained by the rendering engine from HTML’s networking layer.
• Construct the DOM tree: Parsed the HTML to the parsed tree and then set up the DOM tree, making use of it.
• Construct the CSSOM: CSSOM stands for CSS Object Model. Post the construction of the DOM tree, it identifies a link tag in the head section, which references the external style.css CSS style sheet. So, it parsed the CSS file in CSSOM tree, something which the Browser can comprehend as the DOM tree.
• Construct the Render tree: Utilise the HTML DOM tree COUPLED with the styling DATA of the CSSOM tree to set up a render tree. Render tree is the graphical depiction of the HTML, with the corresponding CSS. This tree enables painting the contents in their right order. Every node in the Render Tree is regarded as a renderer. The Render tree looks like this:
• Layout: When the renderer is developed and incorporated into the tree, it does not have a size or position. Computing these values is defined as layout. We use the coordinates system to position the element, such as the position of the root renderer is 0,0. The layout continues recursively via a part of the entire renderer hierarchy, calculating geometric INFO for every renderer that needs it. Beginning the layout process implies allowing every node the EXACT coordinates where it should show up on the screen.
• Painting of the Render Tree: The renderer tree is traversed in this stage and the renderer’s paint() method is hailed to exhibit the content on the screen. For good UX, the rendering engine will aim to exhibit the contents on the screen as soon as possible. It will not stand by until all the HTML is parsed to develop and layout the render tree.

 Listed below are some of the ADVANTAGES of REST WEB services:

• The curve of learning is simple since it works on the HTTP protocol.
• No CONTRACT clears between server and client, so roughly coupled application.
• REST approaches can be effortlessly tested on the browser.
• It also backs multiple technologies for the transfer of, for instance, image, JSON, XML, TEXT, etc.
• It is a LIGHTWEIGHT protocol.

An open-source front-end JavaScript library, ReactJS is used primarily for building user interfaces, especially for one-page applications. Also, it is utilized for HANDLING the view layer for web and mobile apps. React LETS programmers build large web applications that can modify data, WITHOUT the need to RELOAD the page. The main objective of React is to be quick, scalable, and easy. It functions only on user interfaces in the application and corresponds to the view in the MVC template. It can be utilized with a combination of other JavaScript frameworks or LIBRARIES, like Angular JS in MVC.

• Meta tags are passed as PAIRS of name/value.
• Meta tags can INCLUDE data about ENCODING, document title, CHARACTER description, ETC,
• Meta tags fit inside the HTML page’s head tag.
• Meta tags are not displayed on the page but it is to be shown on the browser.

Frontend developers utilize different web technologies to change coded data into user-friendly interfaces. Many among these are Cascading Style Sheets (CSS), JavaScript, HyperText Markup Language (HTML), etc. Mentioned below are brief explanations of these technologies that frontend developers must be acquainted with.

• HTML: HyperText Markup Language depicts the content on the page like buttons, links, headings, paragraphs, and lists. It is the building block of websites and is utilized to define and mark content, so a browser shows it correctly. For instance, on a blog post, an image can be seen as an <img> in HTML code, so browsers will understand that they have to display an image.
• CSS: CSS stands for Cascading Style Sheets and is accountable for the style of your web pages such as animations., colours, and layouts. CSS appears more like a group of instructions that gives structure and style to a webpage than a programming language. It enables programmers to control a web application or website's layout, formatting, and presentation. While HTML depicts elements on a page, CSS is accountable for how users see the content. For instance, it handles the border, alignment, size, of an image in a blog post.
• JavaScript: JavaScript is one of three main elements, in front-end web development, that is required to end up with a web page that can be rendered accurately. It is now challenging to visualize websites without JavaScript as it allows programmers to make the sites interactive. This programming language can transform website content on the basis of a user’s action. For instance, at the top of the page, when you CLICK on the Menu button, it will display a dropdown list of options or when you click on a button, it will toggle back and forth between closing and opening the Menu. JavaScript is great at figuring out the kind of browser being utilised, and then rendering the page in such a way that it is not only compatible with that page, but that it works the way it is designed. Using plugins is made easier by JavaScript. When complicated dynamic interactions are required for a site, JavaScript can be implemented to design its framework instead of simply DEPENDING only on HTML.
• CSS Frameworks, Libraries, and Preprocessors: Once you understand the fundamentals of CSS, then you can begin to work with various libraries and frameworks. These tools were designed as a way to help hasten the development process. Frameworks like Tailwind CSS, and Bootstrap let you incorporate the catalogue of classes into your webpage. Hence, you end up with mobile-friendly and professional designs. There are ample choices on the market and you don't require to know them all. It's often useful to look at related jobs and check what technologies they're employing. Then you can concentrate on the most in-demand skills.
• Testing and Debugging skills: As you are CREATING your application, there will be mistakes in your code that require to be fixed. Debugging is the act of recognizing those bugs and resolving them. Another essential skill to know is debugging. Documenting tests for your code is a way to assure that your code is accomplishing what it is meant to do.
• Version control: The way of tracking and the modifications to the project's code is version control. Git is regarded as a popular software that is utilized to track your code. If your code gets messed up, you can utilize Git to GO back to an earlier version of your code rather than manually rewriting everything. Learning Git also lets you cooperate with others on a team and make modifications to the same code base from various locations. It is advised that you should start to learn Git and use a service like GITHUB to host your projects.