Correcting typing errors
You must make any typing corrections in Terminal before you press Return to issue the command. You cannot set the insertion point by clicking in the middle of a command line.
To correct a typing error, use the Delete key or press Control-H to erase unwanted characters, then retype.
To ignore what you have typed and start again, press Control-U.
You may also use the arrow keys to move the insertion point within the command line. When you start typing, the text will be inserted into the command at the insertion point.