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Practice

Comment

Comments are used by developers to explain the purpose, workings, or changes made to the code, or sometimes to temporarily disable specific parts of the code.


Types of Comments in JavaScript​

  1. Single-line Comment

A single-line comment starts with // and is valid until the end of the line.

Example of using comments
// This is a single-line comment
console.log('Hello, World!'); // This message will be printed in the console

  1. Multi-line Comment

A multi-line comment starts with /* and ends with */. This style is useful for writing comments that span multiple lines.

Multi-line comment
/*
This is a multi-line comment.
The content within these tags will not be executed.
*/
console.log('Hello, World!');

Uses of Comments in JavaScript​

  1. Code Explanation: Comments can be used to explain the functionality, working principle, or the purpose of variables or functions.
Explain code with comments
// Assigning 10 to the variable x
let x = 10;

  1. Disabling Code: Comments can be used to temporarily disable a piece of code for bug tracking, debugging, or temporarily deactivating specific code snippets.
Disable specific code
// console.log("This won't run");

  1. Marking TODOs and FIXMEs: By adding comments with TODO or FIXME tags, developers can easily mark parts of the code that need further work or fixes. TODO is used to indicate tasks that need to be done, while FIXME is used for portions that require corrections.
Marking tasks with TODO comments
// TODO: Implement additional features here

Considerations:​

  • Although comments do not affect code execution, excessive use of comments can reduce the readability of the code. It is advisable to use comments where necessary and appropriately.

  • Avoid including sensitive information or unnecessary personal details in comments.

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