There are two main factors you want to look at when performing a laptop hard drive comparison. First you want to look at the storage capacity of the hard drive. The information and data held by a hard drive is measured in gigabytes(GB). For basic computing functions like surfing the web, checking email, and downloading a reasonable amount of files, a laptop hard drive with 60 or 80 GB will be sufficient. Most laptop manufacturers offer hard drives with storage space ranging from 80 GB to 320 GB, with some offering up to 500 GB. There are multimedia laptops available that have dual hard drives installed with a total storage capacity of 500 GB to 1 TB. Those computers are often known as "extreme" laptops.
The other factor to consider when making a laptop hard drive comparison is the speed of the drives. The faster a drive spins the faster information/data is read and written. The three speeds laptop hard drives usually come in are 4200 RPM, 5400 RPM, and 7200