What exactly are commands? How to identify?
18346
List all commands that a shell knows
120229
Understanding various update and upgrade commands
63791
Are there any utilities to quickly add, list and remove command aliases?
70287
How to get a list of all the commands available for Ubuntu?
144458
How can I tell what command an alias stands for?
52275
How do I use man pages to learn how to use commands?
9023
How do I delete my commands quickly?
3943
How do I search my command-line history for commands I used before?
38529
How do I get help for "echo" or other bash commands?
94205
What is the difference between Fragile and Robust commands?
65718
What's the terminal command for finding out a process's id
94443
What does the 'rc' in `.bashrc`, etc. mean?
109962
How do I list all available shell builtin commands?
72725
What's the difference between \newcommand and \newcommand*?
99250
How do I read the source code of shell commands?
73036
How do I run a command?
3585
What exactly happens when a built-in command is run in a shell?