Output Devices.

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Output Devices

1) HARD COPY DEVICES – PRINTERS

2) SOFT DEVICES - VIDEO DISPLAY DEVICES

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HARD COPY DEVICES

Printers used when there is large volume of data and several copies are normally needed Types of printers

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PRINTER CHARACTERSTICS

LINE PRINTERS

-Large volume output

-fast entire line printed

-multiple copies

-high capital cost but low running cost

DOT MATRIX PRINTERS

- Slow

- inexpensive ( per copy cost)

- multiple copies with carbon paper

- poor graphics

INKJET PRINTERS

- Characters + graphics

- multicolour

- capital cost low compared to laser printer

- recurring cost high

LASER PRINTERS

-Characters + graphics

-multicolour expensive

-excellent quality

-capital cost high

- recurring cost lower than inkjet

SOFT COPY MEDIA

Used to distribute manuals, massive reports, user documents, etc

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• FLOPPY DISK

- Inexpensive

- Easy to mail/transport

- Low capacity –1.4MB

- Read/write

• CDROM

- Inexpensive Medium

- Read only cheaper/safer

- High capacity – 600MB

- Easy to transport/mail

- Primarily used for Text/Graphics

• DVDROM

- Read only cheaper/safer

- Very high capacity – upto 8GB

- Easy to transport

- Useful for storing high quality video such as full length movies

• FLASH MEMORY

- Read/Write

- Small size and weight

- No moving parts thus very reliable

- Needs USB port on PC

- Size 128KB to 2GB

- Low Power needs

- Expensive

SPEECH OUTPUT DEVICES

• Audio such as beeps used for alerting users

• Device used is a speaker

- Very small and inexpensive for beeps

- Inexpensive for poor speech quality

• Useful when eyes are busy, for example, while driving, pilots etc.

• Pre-recorded speech is output in such cases

• Text-to-speech also useful for giving instructions where manuals cannot be read.

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