HowtoMatrix

The Linux command-line can appear pretty complicated and occasionally even a little alarming. But it also offers a whole stack of helpful documentation which you can access directly from the command-line. Read on to learn how to help yourself when – or even before – you get stuck.
apropos

A question you may have quite early on in your command-line exploration is: is there a command that does the thing I want to do? apropos is here to help. Manual pages (I’ll discuss these in more detail below) are available for almost all Linux commands, and include a short description of the command. apropos searches this for the string you provide.
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