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Think of your computer as a series of tubes that can either be 32 or 64 bits wide. When you have the smaller 32-bit size, there is more potential for bottlenecks to occur. Bottlenecks slow down your system because one process has to wait for another to finish before it can begin. But if you want to have 64-bit wide tubes, your computer needs to be thinking in 64-bit so your software and hardware all need to support 64-bit. If you do not know the difference between 32-bit and 64-bit, I would have told you in the past that you are running a 32-bit version of Windows. But now with Windows 7 I am seeing more and more 64-bit operating systems shipped by default without the end users knowledge. Don’t get me wrong, a 64-bit system is better but you also need to be running 64-bit programs and have a 64-bit processor or else all the trouble of setting up the 64-bit operating system would be worthless. On a 32-bit operating system, you are restricted to a maximum of 4 gigabytes of RAM. On a 64-bit operating system, you really do not have a limit. Let’s look at Wikipedia and find out the maximum amount of RAM for a 64-bit operating system: