ALT+F4? ALT+F+X? CTRL+W? CTRL+F4? What are we talking about here? Maybe it will make more sense if I said: Close Program, Exit Program, Close Window, Close File. These are all different ways to get your computer to do similar things using only your keyboard, not your mouse.
I don't know if you remember computers back in the 80's when computers were not as friendly as they are today. Back then if you wanted to do something, like make a word bold, you had to know the proper keystrokes because the mouse wasn't in vogue yet (unless you were a Mac user). To make a word bold, you had to use the control key (CTRL on your keyboard) and hit the letter "B" at the same time (hence, CTRL+B).
Well guess what?!? Those keystrokes still work (most of them that is). I'm not saying you should ditch your mouse but if you want to speed up the way in which you use programs like Word, Excel, Powerpoint or virtually any Windows-based program, you should learn a few shortcut keys.
Get comfortable with the most important key: the ALT key. The ALT key is typically reserved for application level functions - like closing an entire program, switching between applications, etc. The best use of the ALT key is to hit it once and look to the menu bar of your application. Notice that the first menu item (e.g. File) is highlighted.
Now navigate the menu with your arrow keys you may see that each menu item has one letter underlined. If you type that letter on your keyboard you can activate that specific menu and see its contents. For example, hit "H" for the Help menu. Once again you should notice that each menu item has an underlined letter that you can hit to perform the action. For example, hit the letter "A" to see the "About" window for the program. You can hit the ALT key and then type any letter to quickly navigate around your program. HINT: Don't hold down the ALT key to navigate around menus.
Now that you know the basic concepts of the ALT key and underlined letters, you'll start to notice that most actions in a program can be performed with the keyboard, which is much faster than a mouse. But wait, there's more. Here are the shortcut keys I use most:
ALT+TAB - switch between programs
ALT+F4 - close the current program and all related windows
CTRL+TAB - switch between windows within the active program
CTRL+F4 - close only the active window
CTRL+C - copy the selected item (this works on files, text, images, anything!)
CTRL+X - cut the selected item
CTRL+V - paste the copied or cut item
CTRL+S - save your active document (do this often!)
CTRL+Z - undo your last action
CTRL+Y - repeat your last action or redo your last undo
F4 - repeat your last action (this is the best tool in Excel when applying formats
CTRL+ Arrow Keys - move from section to section, especially helpful in Excel
CTRL+SHIFT+ Arrow Keys - select a section, also helpful in Excel
There are lots of other shortcut keys you can learn on your own or by doing a quick search on the web. If you learn just the first one, ALT+TAB, you'll save yourself time and effort. If you learn all of these, you could save yourself 60 minutes a day.