Q. Application and factors related to Scanners?
When you purchase a scanner there are various factors which can be looked at: Compatibility of Scanner with your Computer, The Technology (Depth, Resolution), the media types supported for scanning, how media can be loaded, Media size supported, Interfaces supported, physical dimensions, style and ease of use of scanner.
One exciting application of Scanners is 'Optical Recognition of Characters' (OCR). OCR software attempts to distinguish characters from their shapes and write out scanned text as a text file. Though this technology is steadily refining, it's still not fully reliable particularly w.r.t. Indian scripts. Though it can be very useful to digitize the ancient texts written in Indian scripts.
Scanning technology is also everpresent recent days in Bar-Code readers and MICR (Magnetic Ink Character Recognition) cheques. This technology is very helpful for automating data at source of origin thereby evading problems such as inaccuracies in data entry etc.