Commenting on the code will not only allow you to understand what you have done here, but will also make it much easier for others to work with your code. In addition, with the help of commenting, you can quickly disable those parts of the code that you have not finished yet, but have already added to the page, which is useful when testing. Learn to comment correctly, make life easier for yourself and those around you!
Steps

Step 1. One-line comment
Such comments are formatted with tags. Such comments can be done quickly without much difficulty to remind yourself what a particular piece of code is doing.
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The main thing is that there are no spaces here. For example, the code <! - does not activate the comment. Between tags, however, you can put as many spaces as you like

Step 2. Multi-line comment
Such, as the name implies, already capture several lines, which is useful for explaining complex sections or blocking curious parts of the code.
Heading Long comment. Anything between the tags will be treated as a comment by the browser.Site

Step 3. Use comments to disable code snippets
When trying to catch a tricky bug (error), you can use comments to iterate through the code sequentially. This way it will be much easier for you to put everything back - all you need to do is delete the comment code.
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I'll hide it

Step 4. Use comments to prevent scripts from running in browsers that don't support them
If you write in JavaScript or VBScript, you can use comments to hide scripts from browsers that don't support them anyway. Insert a comment tag at the beginning of the script, finish everything // so that the script still runs - but only in browsers that can.
VBScript