32-bit vs. 64-bit Applications
The difference starts with the processing power of the computer. Not all computers are capable of handling 64-bit applications. Take Windows, for example, the 64-bit version can handle more hardcore processing involving large amounts of data. This means that the computer running 64-bit Windows will run its applications faster and more efficiently, however, a user may only notice the difference when using large applications that use up a lot of computing resources. Generically, 32-bit processing involves 2 GB of memory at any given time, where 64-bit processing can handle vast amounts more.
Thus, 64-bit processing sounds impressive but it requires somewhat impressive hardware to back it up. As technology improves, all computers are slowly making the move towards 64-bit processing. However, if you want to run a 64-bit application, say professional video editing software, you need hardware that is capable of handling 64-bit processing as well as an equivalently geared up operating system.
Generally, you should be able to run 32-bit software on a machine that has a 64-bit operating system. Based on your needs, 64-bit computing may be a vast improvement, but if you don’t require that kind of intense computing power, it may be a waste.