In this tutorial i will talk about how to indent HTML code.

Why indent your code?
Problems:

Hard to figure out where code ends & text/content begins
Hard to see where the (/p) is, even with wrapping turned on

Advantages:

Start (p) & end (/p) are at same level, so it's easy to see that you've closed code & also see where code starts & ends
Easy to differentiate between code & text/content

Spaces or tabs? (Spaces!)

Should you use spaces or tabs for indenting? A debate has raged on this topic for decades, with different developers insisting that theirs is the right choice. WebSanity uses spaces, for various reasons, so that is the right choice, clearly.

Your text editor should let you choose what gets inserted when you press the TAB key: a tab or spaces. Different text editors call that setting different things.