In the context of operating system in general, and Linux in particular, the term “command” means either a command line application or functionality built into the user shell. However, to the end user, this distinction is of little consequence. Both are used in the same way. You input words into your terminal emulator, and it outputs the results. The purpose of this blogpostto list some commands every Linux user should know, or at least know of, in the case of those with a phobia of text-based interfaces. It doesn’t mean to list every useful command, it isn’t a list of the lesser known utilities, and it isn’t a manual. It aims for coverage of the most useful application in day to day life. As such, it’s divided into several categories, corresponding to particular tasks. It presumes no particular distribution, and while not all the programs described will be installed by default in every distribution, most of them will be present, and the others can be found in the re...