Hard Disk
A hard disk is a section in the computer where programs are stored. A hard disk can save and update the files stored on them. The hard disk is enabled when the computer starts. Older hard drives typically used "IDE" or "ATA" cable, modern use a thick but narrow cable, usually red in color called SATA cable. A hard disk/drive unit comes with a set rotation speed varying from 4500 to 7200 rpm. Disk access time is measured in milliseconds, the higher the RPM the faster data is accessed. Also a useful measure of speed for a hard drive is Mb per second as it tells you how quickly information can be written to disk. Capacity is measured in gigabits and can range from 120GB-1TB and it indicates how much a hardisk can store. Examples of harddisk brands include seagate and western digital, and can range from £40-£250 in price, depending on the MB cache and capacity.