PRINTER
A printer will print data from the micro-computer on paper in addition to having it displayed on the screen. A computer print out is referred to as hard copy. There are several types of printers viz:
a) A dot-matrix printer is a high speed printer which prints letters by means of tiny points or dots sticking the paper to make a character. It prints line by line. It is the best for fast printing of a draft copy. Some dot-matrix printers can be produce fast copy of near letter quality appearance;
b) Letter Quality Printers are generally much slower than dot-matrix but are best for correspondence because of their high quality prints.
c) Daisy Wheel Printer is one example of a letter quality printer. Every character is contained on an individual petal of a revolving disc or printing wheel each character. Different type styles can be obtained by changing the disc or daisy wheel.
d) Thermal Printer: is a slower printer which burns character unto a special paper. The characters are a grid or matrix of dots.
e) Laser Printer: It produces a high quality print. It is more costly than other printers.
f) Ink-jet Printers: Ink-jet printers squirt streams of ink on the surface of the paper. The ink dries almost immediately. This printer is slow. The cost is low but can produce multiple colour printing.
Printers fall into three basic categories namely:
1. CHARACTER PRINTERS
Character printer produces a letter at a time on the paper.
2. LINE PRINTERS
Line printers produce a line at a time.
3. PAGE PRINTERS
Page printers print an entire page at once.
4. Printers are also classified by whether or not the head strikes the paper. If the print head strikes the paper, the printer is called an IMPACT PRINTER, if not, it is a NON IMPACT PRINTER.
In the final analysis, it is pertinent to emphasize that the computer hardware system cannot function on its own without the operating system software. The operating system software is required to run or drive the hardware. It ensure that the computer system function; as a total unit. The application programme is also required to instruct the computer to perform specific tasks such as text editing.
REVIEW QUESTIONS
1. What do you understand by computer hardware?
2. Explain the basic component parts of a micro-computer.
3. Where is data stored in a computer?
4. What do the letters CPU stand for?
5. What is the printer used for? Name FOUR types of printers that you know.
6. List and explain FOUR characteristics of computers which encourage human beings to use them to solve problems.
7. List FOUR different input devices and FOUR output devices that you know.
8. What do the term VDU stand for? Explain the purpose of the VDU.
9. What do you understand by the term HARDCOPY?
10. What is the name given to a keyboard device which has a screen attached to it? (VDU).
11. What is the
12. How many types of printers do we have? Explain their difference.