The difference between CRT and LCD monitors is as follows:

CRT

LCD Monitor

1.     It is less expensive than a LCD monitor. 1.     It is more expensive than a CRT monitor.
2.     It takes more desk space. 2.     It takes less desk space.
3.     It uses more energy than LCD monitor. 3.     It uses less energy than CRT monitor.
4.     It uses picture tube technology. 4.     It uses liquid crystal technology.
5.     Its weight is more than LCD. 5.     Its weight is less than CRT.
6.     It is used for personal computers. 6.     It is used for notebook computers, PDAs, cellular     phones and personal computers.
7.     It emits harmful radiation. 7.     It does not emit harmful radiation.

Q. what is printer? Discuss different types of printers.

A printer is an output device that prints characters, symbols and graphics, on paper.

The printed output is called hard copy. Print resolution is commonly measured in dots per inch (dpi). The printers with higher dpi produce higher quality output.

Types of printers

Different types of printers are as follows:

1. Impact printers

An impact printer prints characters and graphics on paper without striking a print hammer or set of pins against an inked ribbon. Impact printers are the oldest print technologies which are still produced. The impact printers are used where low-cost printing is required. Three most common forms of impact printers are as follows:

Dot matrix printers

Daisy wheel printer

Line printer

2. Non-impact printers

A non-impact printer prints characters and graphics on paper without striking paper. Some printers use sprays ink while others use heat and pressure to create images. These printers are faster than impact printer. However, they are more costly than impact printers. They produce no noise during printing. The print quality of non-impact printers is better than impact printers.

Dot-matrix-printers Daisy-wheel-printer line-printer

Different kinds of non-impact printers are as follows:

Laser printer

Inkjet printer

Thermal printer