In order to simplify the task of finding, modifying and re-executing events in the history list, bash also allows simple command line editing, if your keyboard supports the cursor movement (arrow) keys. Every time you press the up arrow key, the shell will move back one event in the history list and display the command line it finds there. If you press the down arrow key then you move forwards through the list again. When the required line is displayed, just pressing the Enter or Return key will re-execute the command line and add it to the end of the history list. If you wish to edit the command line before you execute it, you do this by using the left and right arrow keys to move the cursor along the line to the point of interest. You can then use the Backspace key to delete characters before the cursor followed by typing in the replacement characters. When you have completed your changes to the command line, Enter or Return will execute it.