64- & 32-bit versions of Windows

What's the difference? Quoting from the Microsoft web site: "The terms 32-bit and 64-bit refer to the way a computer's processor (also called a CPU), handles information. The 64-bit version of Windows handles large amounts of random access memory (RAM) more effectively than a 32-bit system."

Most computers sold with Windows 10, Windows 8 or Windows 7 run the 64-bit version. 

How do I determine what I'm running?

For users of Windows 10, Windows 8, Windows 7 or Windows Vista:

1. Click the Start button on your desktop.
2. Open the Control Panel.
3. Click "System."
4. The "View Basic Information About Your Computer" window will open. The last item in the category headlined "System," will tell you whether you have a 64-bit or a 32-bit operating system.

For users of Windows XP:

1. Click the Start button on your desktop.
2. Open the Control Panel.
3. Click "System."
4. The System Properties window will open. This screen gives information about your computer. If you're running a 64-bit version of Windows XP, that fact will appear on the screen. If you're running a 32-bit version, that fact may or may not appear. In other words, you're running a 32-bit version unless Windows tells you specifically that you're running a 64-bit version.