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## Section 3:Recalling Previous Commands

#### Up and Down

you can recall previously used commands simply by using the Up and Down cursor keys.

#### histroy

To view the list of previously executed commands, you can just type history at the command line.

#### ~/.bash_history.

The list of commands is displayed with the most recent command appearing last in the list. This information is stored in ~/.bash_history.

### Using History Environment Variables

$HISTFILE stores the location of the history file.$HISTFILESIZE stores the maximum number of lines in the history file.
\$HISTSIZE stores the maximum number of lines in the history file for the current session.

### Finding and Using Previous Commands

#### Up/Down arrow key

Browse through the list of commands previously executed

#### !! (Pronounced as bang-bang)

Execute the previous command

#### CTRL-R

Search previously used commands

## Section 4:Command Aliases

### Creating Aliases

You can create customized commands or modify the behavior of already existing ones by creating aliases. Most often these aliases are placed in your ~/.bashrc file so they are available to any command shells you create.