Every time I don’t know how to use a command, I type man <command> to get the manual:

This is a man (from manual) page. Man pages are an essential tool to learn, as a developer. They contain so much information that sometimes it’s almost too much.

The above screenshot is just 1 of 14 screens of explanation for the ls command.

Man pages are diveded into 7 different groups, identified by a number:

  • 1 is user commands
  • 2 is kernel system calls
  • 3 is C library functions
  • 4 is devices
  • 5 is files formats and filesystems
  • 6 is games
  • 7 is miscellaneous commands, conventions and overviews
  • 8 is superuser and system administrator commands

Most of the times when I’m in need to learn a command quickly I use this site called tldr pages: https://tldr.sh/. It’s a command you can install, then you run it like this: tldr <command>, which gives you a very quick overview of a command, with some handy examples of common usage scenarios:

This is not a substitute for man, but a handy tool to avoid losing yourself in the huge amount of information present in a man page. Then you can use the man page to explore all the different options and parameters you can use on a command.

The man command works on Linux, macOS, WSL, and anywhere you have a UNIX environment