Is indenting important in HTML? if yes why?

Answer 1

In HTML, indentation helps you pair your opening tags with corresponding closing tags.

If an error shows up or you forgot to close a HTML tag, indentation can help you quickly locate the problem.

Indentation is also easy on the eye. If you revisit your code after a period away from it, you'll be glad that you indented it for readability.

Answer 2

Indentation in HTML is not important to the "internet". White space is ignored by most communications gear, and either compressed, ignored, or dropped. It's important to humans, though.