alias - create shell shortcuts replacing commands strings.
Create a shortcut to clear command:
alias c='clear'
Create a shortcut to history command:
alias h='history'
Change ping command limit (stop after 5 echo request packets):
alias ping='ping -c 5'
Change rm default confirmation settings:
alias rm='rm -i'
Change wget default resume settings:
alias wget='wget -c'
Remove all alias definitions:
alias -a