Computer speakers, or
multimedia speakers, are
speakers
external to a computer, that disable the lower fidelity built-in
speaker. They often have a low-power internal amplifier. The standard
audio connection is a 3.5 mm (approximately 1/8 inch) stereo
phone connector often color-coded lime green (following the
PC 99 standard) for computer
sound cards. A few use an
RCA connector for input. There are also
USB speakers which are powered from the 5
volts at 500 milliamps provided by the USB port, allowing about 2.5 watts of output power. Computer speakers were introduced by
Altec Lansing in 1990.Computer speakers range widely in quality and in price. The computer
speakers typically packaged with computer systems are small, plastic,
and have mediocre sound quality. Some computer speakers have
equalization features such as bass and treble controls.
A
monitor or a
display is an
electronic visual display for
computers. The monitor comprises the display device,
circuitry and an enclosure. The display device in modern monitors is typically a
thin film transistor liquid crystal display (TFT-LCD) thin panel, while older monitors use a
cathode ray tube (CRT) about as deep as the screen size.
Originally, computer monitors were used for
data processing while
television receivers
were used for entertainment. From the 1980s onwards, computers (and
their monitors) have been used for both data processing and
entertainment, while televisions have implemented some computer
functionality. The common
aspect ratio of televisions, and then computer monitors, has also changed from 4:3 to 16:9 (and 16:10).
In computing, a
printer is a
peripheral
which produces a representation of an electronic document on physical
media such as paper or transparency film. Many printers are local
peripherals connected directly to a nearby personal computer. Individual
printers are often designed to support both local and network connected
users at the same time. Some printers can print documents stored on
memory cards or from
digital cameras and
scanners.
Multifunction printers (MFPs) include a scanner and can copy paper documents or send a
fax; these are also called multi-function devices (MFD), or all-in-one (AIO) printers. Most MFPs include
printing, scanning, and copying among their many features.
Consumer and some commercial printers are designed for low-volume, short-turnaround
print jobs;
requiring virtually no setup time to achieve a hard copy of a given
document. However, printers are generally slow devices (30 pages per
minute is considered fast, and many inexpensive consumer printers are
far slower than that), and the cost per page is actually relatively
high.
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