R.L. Dane 
🍵 
I'm not saying you should all go out and set up aliases to enable your various typos and slip-ups, but I honestly don't know why I didn't do this 25 years ago.
alias cd..='cd ..'
AdamThat can also be done as a bash alias, but for some reason, I've never felt the need to.
Maybe if cd had been changedir all along, or something. XD
I think I commented elsewhere on this thread being surprised that unix's mkdir wasn't md like in DOS.
I never aliased that, but I do have a very useful alias called mcd (actually, a function):
function mcd {
#mkdir & cd
[[ $1 ]] && mkdir -p "$1" && cd "$1"
}