The term "smart tabs" is sometimes used to denote a scheme where one uses 1) tabs for indenting, and 2) spaces for alignment.
[1]
[2]
[3]
implementing in Vim
Visible tabs
This is a really really useful setting:
:set list
:set listchars=tab:>-
Or, if you have utf8 support:
:set list
:set listchars=tab:›