What are scanners?
Scanners copy the image of a document -- such as a photograph, or a newspaper article -- and create a digital version of that document so that it can be read by a computer.
What types of scanners are available?
There are two kinds of scanners available to most consumers: flatbed and sheetfed scanners. Most desktop scanners are known as flatbed scanners. The document being scanned rests on a glass plate while the scanning head moves underneath it, reading the information on the document and converting it into digital information. These flatbed scanners are versatile because they can scan flat originals of various sizes. They can even scan small three-dimensional objects (like your hand). Flatbed scanners can also scan slides, x-rays, and other transparent originals when fitted with a transparency adaptor. These are usually bought as add-ons to the scanner.
Sheetfed scanners work a bit differently than flatbed scanners: instead of having a moving scanning head, the sheetfed scanner moved the paper past a stationary scanning head. They were popular for a time because they tended to be less expensive than sheetfed scanners, and took up less space. However, because the paper moved through the device, they were also more prone to misfeeds. These days, most home and small office customers opt for flatbed scanners. The exception to this are document scanners, which are specifically meant to scan many documents quickly and convert them to digital documents, usual PDF files. (And because they are built for speed, they are much less prone to misfeeds.)
Because all-in-one devices -- that come with printers and scanners combined -- are so popular, most people buy flatbed scanners if they want to scan high-quality images, such as photographs. Because of that, many scanners today come with attachments so that you can scan film strips and slides. In addition, many scanners come with software that can help users tweak photographs and illustrations, or convert typed documents into text that can be used by a word processing program.
Like printers, scanners can be very inexpensive, and many are available for $50. As they become more expensive, they include more features, like better quality scanning and larger scan areas (so that you can scan larger documents).
What costs comes with scanners?
Unlike printers, scanners do not use ink or any other kind of consumable. Therefore, once you have purchased the scanner, there should be no other costs.
What are the advantages of scanners?
Ability to scan documents into your PC.
Disadvantages?
None.
