For more tips and tricks like this, be sure to read Command Line Kung Fu.
You can quickly increase your productivity at the Linux command line by using tab completion. Tab completion can save you keystrokes, prevent spelling mistakes, and guide you through complex commands. It works with file names, commands, command arguments, and more.
Using tab completion will quickly become second nature after seeing it in action and spending just a little time experimenting with it on your own.
For more tips and tricks like this, be sure to read Command Line Kung Fu.