Exclamation mark

Bash builtin to substitute with a command found in history. More information: https://www.gnu.org/software/bash/manual/bash.html#Event-Designators.

• Substitute with the previous command and run it with sudo:

sudo !!

• Substitute with a command based on its line number found with history:

!{{number}}

• Substitute with a command that was used specified lines back:

!-{{number}}

• Substitute with the most recent command that starts with string:

!{{string}}