A printer is a hardware attached to a computer, but external to the main case that houses the CPU, Hard drives, and internal components. Computer peripherals allow smooth interactions between the computer and its users.
A printer prints out information on a screen into a physical copy. This is known as “hard copy”. It prints out in color, double-sided, or in book form. This depends on the type of printer. Cartridges are the costliest part of the printer. Check the cost of a new one before buying a printer. This saves you cost of maintenance. Be aware of other possible quirks as well.
PRINTER TYPES AND TECHNOLOGIES
Inkjet printers print out images by spraying small droplets of very quick-drying ink through tiny nozzles(jets) to the paper. inkjet are less expensive and physically smaller than most laser printers. It uses small drops of ink to print text and graphics on paper. An inkjet print-head has a number of nozzles through which ink goes to the paper. What differs from one technology to the next is what causes the ink to jettison from the nozzle to the page. They are mostly used in homes and small offices. Unfortunately, inkjet is slower than laser printers in action. In spite of this, inkjet printers offer good quality printing at a reasonable price. A worthy mention of their pricier ink cartridges is important.
They are costly. Laser printers produce clean documents quietly with an excellent quality. They produce a printed document using a focused beam of laser light and a rotating mirror to reproduce the image of a document as an electrostatic charge on a photosensitive drum. Toner, the “ink” of the laser printer, added, and the charge on the drum attracts and holds it in the image of the document. A sheet of paper feeds from the paper supply and electrostatically charged. The paper rolls over the drum and picks up the toner. Heat is then applied to the toner, it fuses with the paper, and the document completes and placed on the output rack of the printer. This is a simple overview of how the laser printer works. This is also the same process a Photocopy machine operates with.
Larger systems, such as mainframes, use Line printers. Here, an entire line of text prints in one strike. These printers are capable of printing 132 to 168 characters per line. Each character-position has a print chain containing the characters in the printer’s font set. During printing, the chain at each character-position rotates to the proper character and the line strikes through the ribbon to the paper. The character-position then resets and the next line printing. Line printers print letters, numbers, and special characters. They lack the flexibility to produce the vectors needed to create a graphic.
Type Quality of Printers
Draft quality: This type produces low-quality print where print elements used to form the characters are individually visible on the page. Low-end inkjet and dot matrix printers produce draft-quality type.
Near letter quality (NLQ):
NLQ is better than draft quality. The dots or elements that form the characters are partially visible. Printing the character twice with the second pass slightly offset from the first produces an NLQ character. 150 dpi inkjet and dot matrix printers use NLQ as their type quality default.
Letter quality (LQ):
The best type of quality a printer can produce. It produces characters that have solid characters. High-end inkjet, dot matrix, and laser printers produce letter-quality type. A printer producing 300 dots per inch (dpi), is a letter quality printer. 300 dots per inch (dpi) is a print quality measurement used on inkjet printers and dot matrix printers. Letter quality characters appear solid without any gaps showing.