How to use comments in JavaScript

Posted on Jan 28, 2023

Comments are an essential part of any programming language, and JavaScript is no exception. Comments are used to add notes and explanations to your code, making it easier for yourself and others to understand what your code is doing. In this blog post, we will be discussing how to use comments in JavaScript and the different types of comments available.

The simplest way to add a comment in JavaScript is to use the double forward slash (//). Any text that appears after the double forward slash on a line will be ignored by the JavaScript interpreter. For example:

// This is a single-line comment

Multi-line comments in JavaScript are defined using the forward slash and asterisk (/*) at the beginning and the asterisk and forward slash (*/) at the end. For example:

   This is a multi-line comment
   It can span multiple lines

Comments are particularly useful when you have a section of code that is difficult to understand or has a specific purpose. For example, if you have a block of code that performs a complex calculation, you can use a comment to explain what the calculation is doing and why it is necessary.

//Performing a complex calculation
var result = (a*b)/(c+d);

Another good practice is to use comments to add information about the author, the version, and the last modification date of the code. It helps to understand who made the changes and when it was made.

//Author: John Doe
//Last modification: 22/01/2022

You can also use comments to temporarily disable a section of code. This is useful when you are testing or troubleshooting your code and want to quickly disable a specific section without having to delete it.

//Disabling this section of code
//var result = (a*b)/(c+d);

In summary, comments are an essential tool for adding notes and explanations to your JavaScript code. They help to make your code more readable and understandable, both for yourself and others. Whether you are working on a small project or a large enterprise application, comments are an important part of the development process. Remember to use comments in your code to make it more readable, informative, and easy to understand.