The term “computer system” usually refers to a computer and all the input, output, and storage devices that are connected to it. A personal computer system usually includes the following equipment:
- System unit. The system unit is the case that holds the main circuit boards, microprocessor, power supply, and storage devices. The system unit of the notebook computer holds a built-in keyboard and speakers, too.
- Display device. Most desktop computers use a separate monitor as a display device, whereas notebook computers use a flat panel LCD screen (liquid crystal display screen) attached to the system unit.
- Keyboard. Most computers are equipped with a keyboard as the primary input device.
- Mouse. A mouse is an input device designed to manipulate on-screen graphical objects and controls.
- Hard disk drive. A hard disk drive can store billions of characters of data. It is usually mounted inside the computer’s system unit. A small external light indicates when the drive reading or writing data.
- CD and DVD drives. A CD drive is a storage device that uses laser technology to work with data on computer or audio CDs. A DVD drive can work with data on computer CDs, audio CDs, computer DVDs, or DVD movie disks. Some CD and DVD drives are classified as “read only” devices that cannot be used to write data onto disks. They are typically used to accessdata from commercial software, music, and movie CDs or DVDs. “Writable” CD and DVD drives, however, can be used to store and access data.
- Floppy disk drive. A floppy disk drive is a storage device that reads and writes data on floppy disks.
- Sound card and speakers. Desktop computers have a rudimentary built-in speaker that’s mostly limited to playing beeps. A small circuit board, called a sound card, is required for high-quality music, narration, and sound effects. A desktop computer’s sound card sends signals to external speakers. A notebook’s sound card sends signals to speakers that are built into the notebook system unit.
- Modem and network cards. Many personal computer systems include a built-in modem that can be used to establish an Internet connection using a standard telephone line. A network card is used to connect a computer to a network or cable Internet connection.
- Printer. A computer printer is an output device that produces computer-generated text or graphical images on paper.
The term peripheral device designates equipment that might be added to a computer system to enhance its functionality. Popular peripheral devices include printers, digital cameras, scanners, joysticks, and graphics tablets.
The word “peripheral” is a relatively old part of computer jargon that dates back to the days of mainframes when the CPU was housed in a giant box and all input, output, and storage devices were housed separately. Technically, a peripheral is any device that is not housed within the CPU.
Although a hard disk drive seems to be an integral part of a computer, by the strictest technical definition, a hard disk drive would be classified as a peripheral device. The same goes for other storage devices and the keyboard, monitor, LCD screen, sound card, speakers, and modem. In the world of personal computers, however, the use of the term “peripheral” varies and is often used to refer to any components that are not housed inside the system unit.
Comprehension check. Indicate the paragraph where the following ideas are found in the text.
1. When the drive is being used a small light indicator is on.
2. Sound characteristics of different computers vary.
3. This device is most suitable for controlling the position of the cursor.
4. It’s a device to use Internet via a phone line.
5. This system is represented by different interlinked input, output and storage
6. There is a storage device that uses laser technology.