$ Linux Command

Shell

history

Show and reuse shell command history.

shellhistorycommandsbashterminal

Additional Notes

history shows commands previously entered in the shell. It helps you repeat commands, remember workflows, and search what you did earlier.

History behavior depends on the shell and its configuration.

Syntax

history [number]

Parameters

  • options: Flags that change how history behaves.
  • arguments: Values consumed by the shell builtin or script command.
  • command: Command line to run, test, wrap, or control.

Common Usage

  • history: Show command history.
  • history 20: Show recent 20 commands.
  • !123: Run command number 123 in many shells.
  • !!: Run the previous command in many shells.
  • Ctrl+R: Reverse-search history interactively in many shells.

Examples

history

Show saved command history.

history 30

Show the last 30 entries.

history | grep ssh

Search previous SSH commands.

!!

Repeat the previous command.

sudo !!

Repeat the previous command with sudo.

Practical Notes

  • Be careful with passwords, tokens, and secrets in commands; they may be saved in history.
  • Shell variables such as HISTSIZE and HISTFILE control history behavior in Bash.
  • Use history -c carefully; it clears current shell history in Bash.
  • For reproducible work, save important commands in notes or scripts instead of relying only on history.