Ditto. (Though not 20 years).

I use these 3

   alias ls='ls --color=auto --group-directories-first'  # override
   alias l='ls -hF'
   alias ll='ls -hAlF'
   alias lt='ls -clthF'

Also, incredibly useful:

   alias c='clear'

I type `l` and `c` all the time. Then I get on a different machine and `command not found`.