OCR

This means Optical Character recognition.Technique for inputtong text to a computer by means a document reader.First,a scanner produces a digital image of the text;then character-recognition softwere makes use of stored knowledge about the shapes of individual characters and programs based on formal or fuzzy logic convert the digital image to a set of internal codes that can be stored and processed by computer .Sometimes referred to ICR(Intellegent character recognition).
Optical disc:Data storage medium in which laser technology is used to record and read large volumes of dugutal data.Types include CD-ROM,WORMand erasble(meganto)optical read/write discs(CD-R).
Optical fibre: very fine optically pure glass fibre through which light can be reflected to transmit images or data form one end to the other.Optical fibers are increasingly being used to replace metal communications cables,the messages being encoded as digital pulses of light rather than as flucuating electric current.Althrough expensive to produce and install ,opticall fibers can carry more data both faster and with higher band width(range of requwncies )than treditional cables and are less susceptible to interferance.