Information and Communication Technology

2.1.31 Printers 

The fina l output is usually obtained from printers. The paper copy obtained from a printer is often referred to as printout or hard copy . While continuous stationery (paper) is commonly used, single sheet feeding is often possible. Some systems have provision for background printing. This allows the operator to continue to work on the keyboard while the printer is printing another output. Pr inters are available with a variety of printing mechanisms and speeds and varying quality. We could choose a particular printer depending on our requirements. The common categories of printers available in the market are:

1. Impact printers

• Daisy wheel p rinters
• Dot matrix printers
• Line printers

2. Non-impact printer

• Laser printers
• Ink-jet printers
• Thermal printers

Impact printers which have been around for a number of years print by striking the type against the ribbon and the paper (similar to a typewriter). Printers that can print only one character at a time are called character printers as contrary to the line printers which pr int an entire line at a time. They can produce carbon copies, if necessary.

Non-impact printers are practically noiseless and create images only on one copy. They also require special paper but can provide better quality output than impact printers.