Display manual page for a command
Type here
man ls
Show a brief description of a command
Type here
whatis ls
Find the location of a command binary
Type here
which python3
Show all locations of a command
Type here
whereis python3
Display the type of a command
Type here
type ls
Display command history
Type here
history
Search command history interactively
Type here
history | grep python3
Run a previous command by history number
Type here
!42
Repeat the last command
Type here
!!