JavaScript comments can be used to explain JavaScript code, and to make it more readable. JavaScript comments can also be used to prevent execution, when testing alternative code.

HTML comments are not displayed in the browser, but they can help document your HTML source code.

You can use comments to explain your code, which can help you when you edit the source code at a later date. This is especially useful if you have a lot of code.

Comments in PHP A comment in PHP code is a line that is not executed as a part of the program. Its only purpose is to be read by someone who is looking at the code. Comments can be used to: Let others understand your code

The W3Schools online code editor allows you to edit code and view the result in your browser

Java Comments Comments can be used to explain Java code, and to make it more readable. It can also be used to prevent execution when testing alternative code.

Comment Description You can add a message to your comment, to help you remember why you wrote the comment, or as message to other people reading the code.

Well organized and easy to understand Web building tutorials with lots of examples of how to use HTML, CSS, JavaScript, SQL, Python, PHP, Bootstrap, Java, XML and more.

W3Schools maintains a complete JavaScript reference, including all HTML and browser objects. The reference contains examples for all properties, methods and events, and is continuously updated according to the latest web standards.

Well organized and easy to understand Web building tutorials with lots of examples of how to use HTML, CSS, JavaScript, SQL, Python, PHP, Bootstrap, Java, XML and more.