There are so many varying states, or types, of storage.
Which do you choose?
Investigate the types of disk that are available. Begin by becoming informed.
Other than the physical size, you should consider the type of interface.
If you are attempting to replace your main disk drive, the following links show you pictures to identify the interface. You only need to determine the size.
This is a good place to mention that adapters are available for just about everything. A common adapter that I use frequently is a SATA to IDE (PATA) adapter. View. You will not find adapters like these at the local retail outlet, but you can order them from any popular geek web site: www.newegg.com or www.geeks.com .
Your most popular hard drive manufacturers are Seagate and Western Digital.
Solid-State Drives Are Here
Considering that you have used the above links to determine the type of drive that you have and the interface, you need to choose a make and model. If only it was this simple, you have yet a third determining factor now. Do you want a solid state hard drive? I would certainly suggest a solid state drive for extreme laptop users.
Besides being of benefit because of the stability of the drive during transport and mobile use, this drive is much, much faster. You could install the operating system for desktop on an solid-state drive and reap the speed rewards. For general storage and adequate or normal speed, a SATA will do just fine. PATE, or IDE, drives are soon to be obsolete.
In my opinion, if you can manage the cost, a solid-state drive is well worth the purchase and the time to install. If you are faced with a bad hard disk and need a replacement, take a look.