The computer mouse makes navigating your PC easy. However, the mouse isn't always the most efficient way to get computer work done. By taking advantage of keyboard shortcuts, you can shave precious seconds off your workflow and wow your coworkers with your computer prowess. Here are five time-saving keyboard shortcuts to get you started.

Toggle Open Programs: Alt + Tab
This shortcut will save you time if you are used to working with several applications open at the same time. By pressing these keys, a new window will appear displaying the icons of each program that is open. You can toggle these open programs by again pressing the Alt key and then selecting different programs with the Tab key. By releasing the Tab key, the program you selected will now be displayed.

System Lock: Windows + L
The best way to protect your computer from the ill intentions of those around you is to lock it before you walk away. You can do this quickly with two keystrokes, Windows + L. With your PC locked, you can now confidently step away from your desk and take care of business. To unlock your computer, you will need to enter your password, so be sure to know what it is before trying this keystroke. This is not quite as effective if you keep your password on a Post-it stuck to your monitor.

Permanently Delete Files: Shift + Delete
With this keystroke you can save a step when permanently deleting a file. Instead of dragging and dropping the unwanted file to the Recycle Bin, and then opening the Bin and selecting "Empty Recycle Bin," you can permanently delete the files on the spot by selecting the file and pressing Shift + Delete. Press Enter when the menu prompts you in order to complete the procedure.

Show Desktop: Windows + D
When you're working on a project and you need to quickly find a file folder or icon on your desktop, you can do this instantaneously by pressing Windows + D. After you've found what you're looking for on your desktop, you can easily restore your program by again pressing Windows +D. This keystroke can also be used as a great "panic button" because it will instantly hide whatever program you're using. This can come in handy if you're doing something like shopping online to buy your friend a present and then your friend walks into the room.

Maximize Window: Windows + Shift + Up Arrow
Need to quickly maximize your current window? You can do this in a flash by pressing Windows + Shift + up arrow. Just as quickly as you maximized the window you can restore it to its original size by pressing Windows + Shift + down arrow. 

Every little bit of time saved from using keystrokes will add up and make you more productive throughout your workday. These are just five of the most common time-saving keystrokes; there are many more keystroke combinations that you can use to become an efficiency master. Feel free to share with everybody in the comments what your favorite keystrokes are!