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Practice

Comment

Comments are used by developers to explain the purpose, functioning, or changes in the code, or to temporarily disable specific sections.


Types of JavaScript Comments​

  1. Single-line Comment

Single-line comments start with // and extend to the end of the line.

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

  1. Multi-line Comment

Multi-line comments start with /* and end with */. This style is used for comments that span multiple lines.

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

Usage of JavaScript Comments​

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

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

  1. Marking TODOs and FIXMEs: To easily find and fix parts of the code that are under development or need modifications, use comments. TODO is used to indicate tasks that need to be done, and FIXME is used to indicate parts of the code that need fixing.
Marking TODO with a comment
// TODO: Implement additional features here

Note:​

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

  • It is not advisable to include sensitive information or unnecessary personal comments in your code comments.

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