JavaScript is the backbone of modern Web Development. It is one of the most widely used Programming Languages. During the life cycle of a Web application, many Developers work on it to modify and add new functionality, scale the application as users grow, change UI elements to suit different platforms. All these small changes if left undocumented can cause maintenance problems in the future because any new programmer that will work on the application would need to go through and understand the previous developers code. This issue can be mitigated by the use of comments. Comments are an essential part of software development. They do not make the application run faster or perform better, but they make the developer help understand the code and allow for rapid development and clean code.

We can comment our code in JavaScript, add single line comments and multiline comments:

Single line comments in JavaScript

We can write single line comments in JavaScript using two slashes

Multi line comments in JavaScript

We can also write multi line comments in JavaScript. They start with /* and end with */.

A good practice is to write a header above every function header as to what parameters the functions accept, what does the function do with those parameters and what is the return value of the function.

long winded comments describing every line of the code should be avoided. Comments should be concise and to the point but should deliver the necessary information about the code to your future self or any future developer else who works on it.

How do you comment multiple lines in JavaScript?

Multi–line comments start with /* and end with */ . Any text between /* and */ will be ignored by JavaScript.

How do you comment in a script tag?

The comment ends with a “//–>”. Here “//” signifies a comment in JavaScript, so we add that to prevent a browser from reading the end of the HTML comment as a piece of JavaScript code.

How can you add a comment in a JavaScript answer?

How to write comments in JavaScript
  1. Answer: Use the syntax “// text” and “/* text */” Comments in CSS are typically used to explain the purpose of the style rules declarations.
  2. Single-line comments. JavaScript single line comment begins with // , See the example below:
  3. Multi-line comments.
  4. Related FAQ.

What do you mean by comment in JavaScript?

The JavaScript comments are meaningful way to deliver message. It is used to add information about the code, warnings or suggestions so that end user can easily interpret the code. The JavaScript comment is ignored by the JavaScript engine i.e. embedded in the browser.

How do you write a good comment in JavaScript?

Single-line comments are generally used to comment a part of the line or full line of code. Single-line comments in JavaScript start with // . The interpreter will ignore everything to the right of this control sequence until the end of the line.

How do you write a good comment in code?

Primarily, a single “block” comment should be placed at the top of the function (or file) and describe the purpose the code and any algorithms used to accomplish the goal. In-line comments should be used sparingly, only where the code is not “self-documenting”.

How do I comment in JSON?

JSON does not support comments. It was also never intended to be used for configuration files where comments would be needed. Hjson is a configuration file format for humans. Relaxed syntax, fewer mistakes, more comments.

How do you comment on JSX?

Writing comments in React JSX

To write comments in JSX, you need to use JavaScript’s forward-slash and asterisk syntax, enclosed inside a curly brace {/* comment here */} .

How do you comment in VS code?

Comment Code Block Ctrl+K+C/Ctrl+K+U

If you select a block of code and use the key sequence Ctrl+K+C, you’ll comment out the section of code. Ctrl+K+U will uncomment the code.

How do you write notes in HTML?

HTML comment Tag: Main Tips
  1. The <! — –> is an HTML comment tag.
  2. To comment out in HTML, insert information between <! — and –> tags (browsers won’t show these notes).
  3. Commenting in HTML allows developers to leave notes about their code, its functionality or to indicate necessary changes for the future.

How do you add comments in TypeScript?

It is adapted for TypeScript files. Typescript comes with a lot of language annotations, which should not be duplicated in the comments.

To add a comment

  1. press Ctrl+Alt+C twice.
  2. or select ‘Comment code’ from your context menu.
  3. or insert /** above the line of code.

What’s the meaning of comments?

: a spoken or written statement that expresses an opinion about someone or something. : a written note that explains or discusses the meaning of something (such as a piece of writing) : spoken or written discussion about something (such as an event in the news)

What is typescript vs JavaScript?

JavaScript is a scripting language which helps you create interactive web pages whereas Typescript is a superset of JavaScript. Typescript uses concepts like types and interfaces to describe data being used whereas JavaScript has no such concept.

How do I comment in node JS?

To create a single line comment in JavaScript, you place two slashes “//” in front of the code or text you wish to have the JavaScript interpreter ignore. When you place these two slashes, all text to the right of them will be ignored, until the next line.

How do you insert a comment with more than one line?

To comment more than one line:
  1. Select all the lines that you would like to be commented.
  2. Press Ctrl + / Two slashes “//” will be added to the front of each line, causing them to be recognized as a comment.

When was JS invented?

JavaScript
Paradigm event-driven, functional, imperative
Designed by Brendan Eich of Netscape initially; others have also contributed to the ECMAScript standard
First appeared December 4, 1995
Stable release ECMAScript 2020 / June 2020
Major implementations

Is Python or JavaScript better?

Hands down, JavaScript is undeniably better than Python for website development for one simple reason: JS runs in the browser while Python is a backend server-side language. While Python can be used in part to create a website, it can’t be used alone. JavaScript is the better choice for desktop and mobile websites.