A printer is a machine that is connected to a computer and accepts graphics and text output from a computer then transfers the information to paper. There are different types of printers, and their functions vary depending on the technology used in their construction

In general, there are two types of printers:

           Impact printers Impact printing is old technology and printers that use it are very noisy and have poor graphics capabilities. The printer comes into contact with the paper and forms the print image by using a tiny pin and presses it against a ribbon to make a mark on the paper.

       The Dot-matrix is a good example of an impact printer. Dot-matrix printer The dot-matrix printer uses a pinhead that moves across the paper and as it moves, the pins on the print head strike against a cloth ink ribbon that comes in direct contact with the paper, producing each character in the form of dots. Despite being an out-dated technology, dot-matrix printers can print multi-copy documents, such as carbon copies. They are also very durable and can withstand heavy usage over an extended period.

        Non-impact printers These types of printers do not use a striking device to print characters and graphics on the paper, hence are much quieter. They also handle high-quality graphics much better. Some examples of non-impact printers include: 

    a) Inkjet printers These types of printers are commonly used in homes. They are affordable, and they produce photo-quality results. They are also enough to suit the needs of a typical home user.

An inkjet printer works by the print head moving back and forth across the paper while printing. During this process, the print head places ink on the paper in very tiny dots. As these dots are precisely placed, they form to create an image on paper. Inkjet printers use liquid ink in cartridges, with lower end printers having 2 ink cartridges; one for black and the other for colour. Higher-end printers come with 4 ink cartridges. One for black, cyan, magenta and yellow.

    b) Laser printers Laser printers come in different sizes from small personal ones to large ones for businesses. They provide the highest quality print when printing text and graphics. They are also more expensive than inkjet printers. A laser printer basically works by first placing an electric charge on a rotating drum. Then a laser discharges a lower electrical charge on the drum. The laser draws the image that is going to be printed on the drum itself. Then the drum is coated with a fine black powder known as toner. As the drum is being coated, the toner only clings to the areas where the laser has drawn. Then as the paper goes through the printer, the toner is placed on the paper; and the result is a high-quality print.

    c) Thermal printers Thermal printers print by using heat. They use a special print paper known as a thermal paper, and on this thermal paper is a wax-based ink. When heat is applied to this ink, it turns black. So, in a thermal printer, the only thing the print head does is to apply ink to the areas where ink should be printed. Then when the ink is cooled, it becomes permanent. Due to this technology, thermal printers are very quiet. Thermal printers are mostly used for printing labels and barcodes.

    d) 3D printers Image: Pixabay.com Source: UGC 3D printers use an amazing technology where you can take a 3D digital file and with the click of a button, use that file to create an actual digital 3D part. The printer deposits layers of material on top of each other until a physical object is created such as a ball, a face, a cup or any other thing you can think of.

Answer the questions:

1. What are the three types of printers?

2. What is a letter-quality printer?

3. What is a dot-matrix printer?

4. What type of printer is the most common with microcomputer systems?

5. What is the most common printer type used on large computer systems?

6. What is an impact printer? Give an example.

7. What is a nonimpact printer? Give examples.

8. What are the most widely used printers?

9. How do you distinguish between a letter-quality printer and a dot-matrix printer?

10. Which of these printers is slower?

11. What types of character printers do you know?

12. How are printed characters formed by means of an ink-jet printer?

13. What are the main types of a line printer? Which of them is faster?

14. What techniques are used in the operation of page printers?