Does you have ever heard term of RPM ? RPM or abbreviation from Rotation Per Minute is speed ability of rotation from motor at spindle which there is in harddisk.
For temporary, speed of harddisk divided in 3 speed type :
15000 rpm = maximum speed found on harddisk workstation
10000 rpm = maximum speed found on harddisk desktop
7200 rpm = maximum speed found on harddisk mobile PC.
