3 essential Linux cheat sheets for productivity: 
Linux is famous for its commands. This is partially because nearly everything that Linux does can also be invoked from a terminal, but it’s also that Linux as an operating system is highly modular. Its tools are designed to produce fairly specific results, and when you know a lot about a few commands, you can combine them in interesting ways for useful output. Learning Linux is equal parts learning commands and learning how to string those commands together in interesting combinations.
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