Full Tower
ATX Tower
ITX
Mini ITX
Unlike IMacs or dell PCs you can always keep your PC up to date and even change the way it looks. There are many shapes and sizes of computer cases to fit your taste and lifestyle.
The upgradability of your computer is determined by the computer chassis you select, as there are internal components, such as some graphics cards, that are much larger than the computer case itself. There are four popular kinds of computer component housings: Large (Full Tower), Medium (ATX Tower), small (ITX) and very small (Mini ITX).
Obviously, a large tower will be the most flexible in terms of components selection while a very small chassis will be the most limited.