C

Cache: A temporary storage area used to speed up different processes. A web browser keeps recently used web pages on hard disc cache, so it doesn't have to download the same page again. A processor stores recent or frequently used instructions in small chunks of very fast memory called level 1 and 2 caches.  

CD/DVD-ROM: Most computer applications come on CD-ROM disks. The newer DVD drives are quipped to read these older disks as well as the new multimedia format. CD and DVD drives that can write information to a CD or DVD are designated CD-RW and DVD-RW.(RW=Read/Write)

CD-ROM: Compact Disc-Read Only Memory, a CD stamped with data that cannot be erased and filled with new data.  

CD-RW drive: A CD-ROM drive that stores multimedia data on recordable (CD-R) and rewritable (CD-RW) discs. You can use the discs for creating backups on the road or for your favorite music mixes. The upcharge is $100 to $150 over a standard CD-ROM drive; a combination DVD/CD-RW drive is $200 to $250 extra, half what it was a year ago.

Chipset: A collection of integrated circuits on a circuit board that are designed to be used together for some specific purpose. A chipset is usually made up of 1 - 3 main chips.  

CMOS: Complementary Metal Oxide Semiconductor. A process used to make chips, but in a PC is short for a battery-powered chip on the motherboard which stores basic system configurations and clock settings.

CompactFlash card: A storage device for digital devices: CompactFlash (CF) cards. Each measures 43 x 36 x 3.5mm. in addition to solid state memory, companies are manufacturing CF sized hard drives, Ethernet connections and modems, as well as wireless connectivity solutions.  

Contrast: A measure of the brightness difference between pixels that are on and those that are off. Contrast is usually expressed as a ratio such as 20:1 or 100:1. The higher the contrast, the more distint the images appear.

CPU: Central Processing Unit, also called microprocessor or processor. This silicon chip acts as the brain of the computer and carries out tasks allocated and assigns tasks to other resources.