assigns a new name to an existing utility
eg. aliaswill display all the aliases currently set eg. alias dir=ls eg. alias ls='ls -al' eg. alias clearfile='cat /dev/null >' can be useful, but can also make your scripts cryptic your scripts won't be useable by others, unless they use the same aliases
!num - re-execute command number "num"
!xxx - re-execute last command beginning with string "xxx"
=INVESTIGATION 1: LINKING FILES=