Care of Your Computer's Harddrive/Hard Disk (Mass Storage System)

Your computer's harddrive/hard disk is an essential piece of your hardware for storing vast amounts of information. It's located inside the computer box in a sealed aluminum container surrounded by other electronic components. Other than gently blowing off the dust every once in a while there is no other external maintenance required. Amazing really! The hard disk must spin billions of revolutions in its lifetime and relatively speaking, requires very little servicing! That does not mean though, that it should be ignored. Regular maintenance of the data on the hard disk is crucial!

How does it work?

When a computer saves information onto a hard drive, the operating system looks for (seeks) available sectors (empty spaces of 512 bytes long) on the surface of the disk and tries to write the information onto a continuous sequence of sectors. (See "How Hard Disks Work" below for pictures!) It works very well when the operating system has a lot of room (tracks and sectors) to save information. But as the hard disk fills up (read... we copy our entire collection of 500 CD's or save all 5000 digital photographs on the hard disk) it becomes increasingly harder to find consecutive sectors in which to store the information. Whereas it is very efficient to access the whole contents of a file over continuous sectors, having to read or write contents spread out over multiple discontinuous sectors becomes inefficient.

This inefficiency stems from having to make multiple passes over the hard disk surface to read or write information, leading to a noticeable slowdown. When a file is written over several discontinuous sectors, it is said to be fragmented. A severely fragmented harddrive tends to take longer to load up or save files. Programs may even hang or crash if the computer is not able to access the data. A weekly schedule of checking the health of your hard disk can prevent a lot of headaches.

Please read the article called "How Hard Disks Work" for more background information. In general "How Stuff Works" is an excellent source of computer information for future reference.