This is a nifty little trick for making Bash a little more intuitive (for my taste). Usually, when you press the up key, Bash will bring back the last command you typed. This is cool, but what bothers me is that sometimes I start typing a command and then remember I executed it before. So I press the up key and… Bash shows me the last command, disregarding what I typed. What I want it to do is search history for things with the prefix I entered.