A brief overview of how it works, how you would choose a scanner will be covered here. A scanner is similar to digital cameras. A scanner converts an image, printed text, or handwriting, or an object to a digital image.

A flatbed scanner which is the most common in offices converts any printed or reasonably flat material, such as photographs, into digital image. To the extent that it has a glass plate under a lid, and a moving light that scans across under it, the flatbed scanner is very much like a copy machine. A document scanner creates digital records of a range of documents, especially for paper office documents. The film scanner allows you scan a film.

In order to operate the scanner, we need to use software. Scanners usually come with software, such as Adobes Photoshop product, that lets you resize and modify a captured image. An application such as PhotoShop uses the TWAIN program that is a software standard that all the scanner manufacturers agree to use, intended so that all image programs can operate all scanners to read in the image.

Functions in Scanners. Scanner resolution (the sharpness of text and images on paper) is usually measured in dots per inch (dpi), whereas cameras are rated in total pixels. Most basic scanners provide sufficient resolution for most purposes.

Basic scanners scan about 3 to 4 sheets per minute. But expensive scanners are much faster. You have to consider the speed of the scanner if you do much scanning.

Basic scanners come with a small amount of memory (usually, one megabyte) that can be expanded by the user. It is helpful and faster when scanning larger or more detailed images with having more than one megabyte of memory.

Consider your budget and the features the scanner offers before you buy a scanner.