If you are like a lot of people, there are keys on your keyboard that you never use. What are PrtScr, SysRq, and ^? Well, I could tell you but the I’d have to Esc you, so let’s save those for later and deal with the Windows Key today.
The Windows Key lives on the lower left part of your keyboard, next to Alt and pretty close to Z.

What does it do? Press it and see. Go ahead, it won’t hurt anything. Press it, watch what happens, then press it again to reverse the event.
The windows key does the same thing as clicking the Start button with your mouse. It opens the Start menu, so you can see your main menu, programs, etc.
Pressing the key a second time simply makes the menu go away.
This is useful because you can access a vital function of your PC with a press of a button. You’re not confined to using the mouse. And in Windows 7 your Search programs and files function is the first thing on the bottom of the menu.

I’ll admit that I didn’t use the Windows Key for years. But now, and for a long time now, I do it without even thinking. That little Search element is my constant friend. I use it to quickly find documents and folders, and I use the larger Start menu to open programs, access photos and videos, navigate to My Computer, My Dropbox, etc.
Get to know your Windows Key. It will come in handy, you’ll see.