ASCII ( ), abbreviated from American Standard Code for Information Interchange, is a character-encoding scheme (the IANA prefers the name US-ASCII). ASCII codes represent text in computers, communications equipment, and other devices that use text. Most modern character-encoding schemes are based on ASCII, though they support many additional characters. ASCII was the most common character encoding on the World Wide Web until December 2007, when it was surpassed by UTF-8, which includes ASCII as a subset..
A typewriter is a mechanical or electromechanical machine for writing in characters similar to those produced by printer's movable type by means of keyboard-operated types striking a ribbon to transfer ink or carbon impressions onto the paper. Typically one character is printed per keypress. The machine prints characters by making ink impressions of type elements similar to the sorts used in movable typeletterpress printing.
The Universal Product Code ( UPC) is a barcode symbology (i.e., a specific type of barcode) that is widely used in the United States, Canada, the United Kingdom, Australia, New Zealand, and in other countries for tracking in stores. Its most common form, the UPC-A, consists of 12 , which are uniquely assigned to each trade item. Along with the related EAN barcode, the UPC is the barcode mainly used for scanning of trade items at the point of sale, per GS1 specifications.http://www.gs1us.org/standards/barc..
