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Computer Awareness is one of the most important subjects that come in the Banking exam. However, not many candidates pay a great deal of attention towards this particular subject.
Computers form the basis of the working any organization in today’s age. If you are looking forward to working in a bank, then you need to have a basic understanding of computers. This is exactly what this section of the exams tests you for.
Here We have listed the important of Computer Awareness Study Material for competitive exams. Here we are providing Study Notes of Computer.
Computer Awareness Study Notes on Printers & its type
Printer is among the most common output device, which is used to print information on paper. It is an output device to produce paper copy (hard copy) for a document, pictures etc. The job of a printer is to put on paper what is seen on the monitor.
Types of printers
The printers are classified as under:
• Impact Printers – These printers have a mechanism that touches the paper in order to create an image. The Dot Matrix Printer is an example of this type.
• Non-impact Printers – These printers do not touch the paper when creating an image. The inkjet and laser printers are examples of this type.
Impact Printers
An impact printer is a type of printer that works by direct contact of an ink ribbon with paper. A metal or plastic head strikes the ink ribbon, whereby the ribbon is pressed against the paper and the desired character (letter, digit, dot, line) impression is printed on the sheet. Dot matrix, daisy-wheel and ball printers are some commonly used types of impact printers.
As the name suggests, an impact printer physically impacts the sheet of paper.
Types of Impact Printers
Different types of Impact printers are as follows:
Dot Matrix : The term dot matrix refers to the process of placing dots to form an image. Its speed is usually 30 to 550 characters per second (cps). This is the cheapest and the most noisy printer and has a low print quality. Dot Matrix were 1 st introduced by Centronics in 1970.
Chain : A chain printer has a set of metal characters and numbers arranged in a continuous loop, resembling the blade of a chainsaw. Behind the paper, a row of hammers strike the characters as they come around on the chain. The chain mechanism has print speeds up to several hundred lines per minute, faster than a dot matrix. The chain printer is also more expensive than a dot matrix, as it is more complicated mechanically. Its character set is limited to whatever the chain contains; graphics made with a chain printer are primitive at best. Like a dot matrix printer, a chain printer is somewhat noisy.
Daisy Wheel: A daisy wheel printer is basically an impact printer consisting of a wheel and attached extensions on which molded metal characters are mounted. A daisy wheel printer produces letter quality print and it can’t produce graphics output.
Drum : Drum printers share features with chain printers; both print at high speeds. Here, a metal drum roughly the size of a baker’s rolling pin has raised characters formed into its surface. As the drum rotates, electric hammers strike the paper, forcing it against a ribbon that sits between the paper and the drum. The print drum is quieter than a chain, as the drum makes no noise as it rotates, unlike the clatter a chain makes as it spins. As with the chain printer, it prints only the characters on the drum.
Non-impact Printers
It is a type of printer that does not hit or impact a ribbon to print. They used laser, xerographic, electrostatic, chemical and inkjet technologies. Non-impact printers are generally much quieter. They are less likely to need maintenance or repairs than earlier impact printers.
Non-Impact printers are faster and produce hight quality output than impact printers. They can print up to 24 pages per minute. They produce no noise during printing. These printers are costly than impact printers
Types of Non-impact Printers
Different types of non-impact printers are as follows:
Laser Printer : Laser stands for light amplification by stimulated emission of radiation. The laser printer is a non-impact printer. Its working is similar to photocopying machine. It uses laser beams to burn special powder on page to create a permanent image. The power is contained in toner. Laser printer prints complete page at a time. It is also known as page printer.
Inkjet Printer : An ink-jet printer is a type of non-impact printer. It prints characters and graphics by spraying tiny drops of liquid ink on paper. These printers can produce quality text and graphics in both black-and-white and color including photos. A typical inkjet printer provides resolution of 300 dots per inch. The latest inkjet printers provide higher resolution.
Thermal Printer : Thermal printer uses color waxes and heat to produce images on special paper. The color wax sheets are not required for black-and-white output. Thermal printers are expensive and require costly paper. These printers are used to create the highest-quality color printing.
