Ubuntu by default has an alias to point to ls.
I find it much better to use a customized tree command instead.
Contents of file ltree:
#ls --color=always $argu | less -R
tree -C $argu | less -R[/code]
I add the following to ~/.bashrcalias dir='ltree'[/code]
Now on executing dir, I get a beautiful colored hierarchy of directories and files.
Other useful aliases are:
la='ls -la' #Included by default in Ubuntu