[necovek]

In practice, I don't care, and I lol-ed at the religion comment below.

And I know tabs are seeing a comeback lately, but they are basically the only ASCII character that does not have a predefined width.

And the reason I dislike that is because they don't have clear semantics even in the pure text-only world: eg. writing out a table in ASCII is not possible with these "tabulating" characters, because if the column data is wider than (tab-width – 1), well, there goes your alignment. And when something is so badly defined not to serve the purpose it's named after, I can't like it. :)

If it was called the "indent" character which was ignored anywhere but at the start of the line, it would at least be sane and consistent.

Incidentally, Emacs can do the right thing in most modes by turning tab key into the (re)indent command.