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Inkjet Plotter: In this type of plotter, jets of ink is used in place of ink pens. The paper is placed on a drum
and inkjet with different coloured inks mounted on a carriage. Inkjet plotter can print multicoloured large
drawings.
Speaker
Speaker is an output device that converts the electrical signals into sound waves that we hear. In speakers, the
electric current of the music files is supplied to the magnet that pushes the diaphragm of the speaker back
and forth. This creates pressure and vibration in the air and as a result, sound is produced.
Monitor
Monitor is a standard output device. It is also known as VDU (Visual Display Unit) or Screen. Monitor is used
for interactive processing i.e., the data being fed is displayed on the screen. It resembles a television.
The monitor is connected to the video adapter or video card of the motherboard inside the computer.
Monitors can be either monochrome or coloured. In a monochrome screen (though rarely used) there is only
one colour (usually white, green, amber or black). The monochrome monitor’s display is only in Black and
White. In colour screens, there can be a colour combination of up to 2,56,000 colours on the monitor. The
screen of the monitor is normally measured diagonally and is available in different sizes like 15”, 17”, 21”, 34”,
etc. The screen of a DU is divided into specific character positions.
In the graphics mode, the pictures are displayed by a combination of dots. The screen is treated as an array of
tiny dots called ‘Pixels’. In the graphics mode, there is a resolution of 640 dots across and 480 dots vertically
on the screen. There are different types of adaptors that support the display of graphics.
The higher the resolution, i.e., the more the number of pixels, the better the quality of the picture that
is displayed on the screen. DPI (dots per inch) is the unit of measurement of resolution applied to printers,
scanners, monitors, etc. Many computer systems and portable devices like laptops, PDAs, etc. have Liquid
Crystal Display (LCD) or LED monitors.
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