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JavaScript Comments

Comments in JavaScript are used to provide explanations or annotations within the code. They make your code more readable and easier to understand by others or yourself in the future. Comments are ignored by the JavaScript interpreter and do not affect the code execution.

In this tutorial, we'll learn about the two types of comments in JavaScript: single-line comments and multi-line comments.

Single-Line Comments:

Single-line comments start with two forward slashes (//) and continue until the end of the line. Everything after the slashes is considered a comment and will not be executed.

Example:

// This is a single-line comment

let x = 5; // Declare a variable and assign it the value 5

In the example above, the first line is a single-line comment. The second line contains a single-line comment after the code, providing a brief explanation of the code's purpose.

Multi-Line Comments:

Multi-line comments start with a forward slash followed by an asterisk (/*) and end with an asterisk followed by a forward slash (*/). You can use multi-line comments to write longer explanations that span multiple lines.

Example:

/*
This is a multi-line comment.
It can span multiple lines without any issue.
*/

let y = 10;

In the example above, the first four lines are a multi-line comment that provides a more detailed explanation. The comment ends on the fourth line, and the JavaScript interpreter continues executing the code from the sixth line.

Conclusion

Comments are essential for making your JavaScript code more readable and maintainable. Use single-line comments for short explanations and multi-line comments for longer descriptions or to temporarily disable sections of code during development. Remember, comments do not affect the execution of your code and are ignored by the JavaScript interpreter.