How to tell if pc is 32 or 64 bit

32-bit and 64-bit Windows: Frequently asked questions - Windows Help
The 64-bit version of Windows handles large amounts of random access memory (RAM) more effectively than a 32-bit system. How can I tellif my computer is running a 32-bit or a 64-bit version of Windows?

How to determine if Windows OS is 32-bit (x86) or 64-bit (x64)
Usually titled 64-Bit or 32-Bit, these programs are generally identical to each other but either do not function properly when installed on the