Office computers can get by on simple cards with as little as 4 megabytes of memory, but improved video and a good monitor can ease eyestrain. A card that translates data from the computer into signals that can be sent over telephone lines. Some computers can get by without a sound card, relying on a tiny speaker provided with the box that only beeps. Gamers, of course, want cards that offer multiple channels capable of re-creating the sounds of World Wide Conflict. Some people with disabilities want sound cards to handle speech recognition programs.
Compact discs are media for data storage.
You can play your music CDs in a computer, but you can't play computer CDs, even those with sound files, on your music player. A CD-ROM player on a computer can read information off a CD, but it cannot write memory onto a disk. Because CDs can hold up to 650 megabytes, they can be used to back up all of your data, providing a safety net in the event of a hard drive failure, a virus or other data losses. For years, DVDs have been used mostly for movies, but some programmers are taking advantage of DVDs' superior video and storage capacity. It's not a television because it doesn't have a tuner, but you can buy a tuner for your computer and complete the package.