Output device: Printer definition, History, Characteristics, Function, Types of Printer, Advantages & Disadvantages, Interface Hardware & Networking

 Definition: 

A Printer is a hardware output device that takes the electronic data stored on a computer or other device and generates a hard copy. A document can be of any type such as a text file, image, or the mix of two. It accepts input command by users on a computer or any devices to print the documents. The printer can be both black and white and color images.

Content:

1. Definition
2. History
3. Characteristics
4. Function
5. Types of Printer
6. Interface
7.  Q&A

For example, if you have to submit a project report at your office, you need to create a soft copy of your report and print it with the help of the printer.

History: 

Over the evolution of the printer, there were several types of printer developed. So, there is no single inventor to invent the printer. The first computer printer designed was a mechanically driven apparatus by Charles Babbage for his Difference Engine in the 1800s. See the next section for a list of different printers and their inventor.  

Mechanical Printer	Charles Babbage designed the first mechanical printer in the 1800s, for use with the Difference Engine
Dot Matrix Printer	n 1957, IBM created the first dot matrix printer.
Inkjet Printer	inkjet printers were developed in 1950s. Epson, Canon, and Hewlett-Packard companies were developed Inkjet printers.
Laser Printer	The laser printer was developed by Gary Starkweather during working at Xerox by modifying one of their model 7000 copiers in the beginning 1970s.
3D Printer	n 1984, the 3d printers were introduced by Chuck Hull.

Characteristics:

Print Quality: The quality of printed output is describe as being letter quality, near letter quality, or draft quality.

Speed: It determine how quickly printer creates output, measured in character per second or pages per minute. Daisy-wheel printers are slowest, printing about 30 cps. Line printers ae fastest (up to 3000 lines per minute). Dot-matrix printers can print up to 500 cps. laser printers range from about 4 to 20 text(ppm).

Resolution: It create clarity of printer output, measured in dots per inch (dpi). Which describes the density of ink dots used to create printed output.

Memory: Used to store the text or images information before printing the documents. The more memory a printer has, the more efficiently it can print out pages.

Fonts: Some printers, notable dot-matrix printers, are limited to one or a few fonts. In contrast, laser and ink-jet printers ae capable of printing an almost unlimited variety of fonts. Daisy wheel printers can also print different fonts.

Color: Pinter’s are capable to print in color in black and white. Or just black and white.

Function of Printer:

Now days everywhere use printers to print documents. Here we will see various uses of printers -------------

·        Printing Documents:

Printing is the main function since the first release of printer in the market. This machine is able of printing text for office documents or school assignments.

·        For Printing Photos:

Nowadays, printers are widely used to print photos. Using the advanced technology, we can even print our photos at home if needed. Professional photo printers (Canon PIXMA G570 and PIXMA G670) provide 2 additional inks besides black, cyan, magenta, and yellow.

·        Scanning and Copying:

There many various types of printers are available in the market and one of them is a multifunction printer. The all-in one printers are commonly used for offices or homes usually have 3 main functions, print, scan, and copy.

·        For sending Fax:

Sending physical files that do not have digital forms to other places can be done with a fax machine. This function is very practical to use in offices because documents can be sent quickly to other places. Nowadays, fax machine are no longer widely used as they used to be. Because today documents are often scanned and sent via e-mail.

Types of Printer:

Printers are mainly divided into two categories based on the method of printing ----------------

1. Impact Printers
1. Character Printers

                                          i.    Dot Matrix printers

                                         ii.    Daisy Wheel printers

2. Line printers

                                          i.    Drum printers

                                         ii.    Chain printers

2. Non-impact printers
1. Laser printers
2. Inkjet printers

1.   Impact Printer:

An impact printer makes contact with the paper. It generally forms the print image by pressing an inked ribbon against the paper using a hammer or pins. These printers are generally loud but stay in use today because of their unique ability to function with multipart forms. 

A.      Character Printer:

Character Printer are defined as impact printers. It can print one character at a time instead of one line at a time. Today, these printers are rarely used because of speed issued and because only text is capable of being printed.

Character printer are categorized into the following two types:

                                                             i.      Dot Matrix printers:

Dot Matrix Printers are the most popular type of impact printer. These printers have a matrix of pins on their print heads to create character or graphics.

 Dot Matrix printers uses print heads containing from 9 to 24 pins. The 24 pin dot-matrix printer produces more dots that a 9 pin dot-matrix printer, which results in much better quality and clearer character. The general rule is the more pins, the clearer the letters on the paper. These types of printers are generally used to print the shipping invoices.

Advantages:

1. This printers are cheap and easily available in the market.
2.  They can make carbon copies of the print out unlike no impact printers.
3.  The printing costs are the lowest as compared to other printers.

Disadvantages:

1. The output is not high resolution. The quality of print out in general is not very good. 
2. Color printout is limited and the print speed is also less as compared to non-impact printers.
3. It create high noise when the pins hit the ribbon to the paper.

                                                           ii.      Daisy Wheel printers

Daisy wheel printers are impact printers used primarily to achieve the quality found with typewriters. Because these printers are looks like a daisy (a flower), they are named daisy wheel printers. Daisy wheel printer print only characters and symbols and cannot print graphics. They are generally slow with a printing speed of about of 10 to 75 characters per second.

Advantages:

1. Low maintenance
2.  Low costs
3.   It can create carbon copies
4.   Better print quality than a dot-matrix printer

Disadvantages:

1. Noisy printing
2. No graphics
3.  Limit number of character

B.      Line Printer:

Line printers, also called bar printers. Line printers is a type of impact printer that usually print an entire line at a time. This printer is a form of high speed impact printer. It 300 to 3000 Lines per minute. So, they are very fast. Large computer system is typically using Line printer.

Line Printers are categorized into the following types:

i.       Drum Printer:

The Drum printer consists of a Drum which consists of number of characters, those are printed on the Drum. And the number of character are divided after examining the width of the paper. But there are also some character sets available. For Example 64, and 96 characters etc.

          ii.  Chain Printer:

These are also Line printers, which prints one line a time. These printers have a character set of 48, 64, or 96 characters. The chain is connected using gears in such a way that if can rotate horizontally like drum printers. It has several hammers. The total number hammers is exactly equal to the number of print positions.

2. Non-impact Printer:

Not-impact printer do not use a striking device to produce character on the paper. And because these printers do not use hammer against the paper they are much quieter.

 some Non-impact printer are given below ---------------

A.    Laser Printer:

Laser printer are non-impact printer. It is one of the common personal computer printers. It was introduced in 1971, after that it was developed at Xerox PARC by Gary Starkweather. This printer works like a photocopy machine. It uses non-impact photocopier technology to print the text and images on the paper. Whenever it gets input to print any document, a laser beam draws the document on the selenium-coated drum with the help of electric charges.

Advantages:

1. The main advantage of Laser printer is its speed and efficiency.
2. It prints high quality and graphics and text.
3.  It has a higher paper capacity.
4.  it is able to increase productivity.

Disadvantages:

1. The main disadvantages of Laser printer is its cost, they are relatively costly as compared to other printers.
2. The maintenance, repair and servicing charges are also high of these printers.
3. It may need warm up time.
4. It requires high voltages leads to small carbon emissions.

B.  Inkjet Printer:

Inkjet printers are non-impact printers. It is widely used by home and business computer. This printer prints characters by spraying the ink using magnetic plates on the paper. t contains a paper feed assembly, ink cartridge, print head, stabilizer bar, and belt. t stores the ink in cartridges, and uses separate cartridge to print several types of color documents. These colors are mixture of cyan, magenta, yellow, and black color.

Advantages:

·         The Inkjet printers have the power to provide top quality output..

·         The Inkjet printers do not require time to heat the machine system before print.

·         This type of printer is considerably cheaper to buy.

Disadvantages:

1.  It may take time to print.
2. Its running cost is high.
3.   Sometimes, it will turn out wrong warning of an empty cartridge.

Printer Interfaces:

 There are a few different ways a printer can connect to and communicate with a computer Below is a full list of cables and interfaces used to connect a computer to a printer.

1. Cat 5 cable
2. Firewire
3. MPP-1150
4. Parallel port
5. SCSI
6. Serial port
7. USB
8. Wi-Fi

Question and Answer:

1.     What is hard copy?

A hard copy is printed copy which output in a printer.