How to use the look command: 2-Minute Linux Tips
In this Linux tip, learn how to use the look command. It allows you to easily pick out lines that begin with a given string from a file that you specify. The look command only matches beginnings of lines and doesn’t work with wild cards. For more complex searches, you’re better off using grep which isn’t limited to the beginnings of lines and has a lot more options.
Source:: Network World – Linux