In the past, people ran 64-bit windows only when they really needed to. With several advanced features such as being able to address more than 4 GB of ram, windows 64-bit systems are becoming more prevalent. Most 32-bit applications install and run fine on 64-bit systems. There are times, however, when it is important to install the specifically made 64-bit product. This is typical when installing device drivers and computationally intensive applications.
How to determine if you are running 32-bit or 64-bit Windows
Right-click on the menu item “Start – Computer”
Right-click on “Computer” on the desktop
In the resulting window, look in the “System” section for your answer