Difference between Printer and Scanner

1. Printer : A printer is an external hardware output device whose work is to acquire the text and graphics output from the computer and generate a hard copy of it. So, basically it processes the soft copy and produces its hard copy. There is a wide variety of printers based on their speed, cost, size, quality of the hard copy produced and complex construction. Mostly, the cost of printers increases as the quality of printing increases. The first computer printer designed was a mechanically driven apparatus by Charles Babbage for his difference engine in the 19th century; however, his mechanical printer design was not built until 2000. Features of Printer:

1. Print Speed - It is good to have a printer which prints at least 10 color pages per minute and 20 black-and-white pages per minute.
2. Printer Quality - Black-and-white printers should have a minimum resolution of 600 x 600 dots per inch and color print quality of 1200 x 1200.
3. Duty Cycle - A printer’s duty cycle is the maximum number of pages that should be printed per month. Normally it ranges from 20k-25k pages per month.
4. Ink Replacement Costs - It is the yield that can be expected from the ink or toner cartridge.
5. Copy Speed - Once the scanner has created a reproduction of the image the user wants copied, the speed at which copies of that image are produced is important.

2. Scanner : A scanner is an input device that regenerates an image from a source object, generating an identical image for display or processing. More specifically, it scans documents such as photographs and pages of text and then convert them into a digital format. This generates an electronic version of the document that can be viewed and modified on the computer. It is a machine that recognizes optical characters. Feature of Scanner:

1. Resolution - It refers to the quality of the scanner which is based on how many pixels it is able to sample.
2. Scanning Area - The scanning area simply refers to the document size a scanner is able to accommodate.
3. Compatibility - It refers to the ability of scanner to work with other software and computer parts.
4. Scanning Speed - Generally high quality resolutions will require longer scanning times and thus, scanning speed contribute to one of the important feature of scanner.
5. Scanning Method - There are two types of scanning methods that are used, namely the charge-coupled devices, or CCDs, and contact image sensors, or CIS.

Printers	Scanners
It is a device whose work is to acquire the text and graphics output from the computer and generate a hard copy of it.	It is a device that scans documents then convert them into a digital format.
Output Device	Input Device
Digital document is rendered over the paper by creating an impact or charges on a photosensitive material.	Illuminating lamp is used on the scan head to reflect the light on to the lens, which is then focussed over a CCD array.
Examples are Laser Printers, Solid Ink Printers, LED Printers., Business Inkjet Printers, Home Inkjet, Printers, 3D Printers.	Examples are Flatbed, Sheet-fed, Handheld, and Drum scanners.