Optical character recognition (OCR) is the electronic identification and digital encoding of typed or printed text by means of an optical scanner and specialized software.
Using OCR software allows a computer to read static images of text and convert them into editable, searchable data.
OCR typically involves three steps: opening and/or scanning a document in the OCR software, recognizing the document in the OCR software, and then saving the OCR-produced document in a format of your choosing.

Widely used as a form of data entry from printed paper data records – whether passport documents, invoices, bank statements, computerized receipts, business cards, mail, printouts of static-data, or any suitable documentation – it is a common method of digitizing printed texts so that they can be electronically edited, searched, stored more compactly, displayed on-line, and used in machine processes such as cognitive computing, machine translation, (extracted) text-to-speech, key data and text mining. OCR is a field of research in pattern recognition, artificial intelligence and computer vision.
Advanced systems capable of producing a high degree of recognition accuracy for most fonts are now common, and with support for a variety of digital image file format inputs. Some systems are capable of reproducing formatted output that closely approximates the original page including images, columns, and other non-textual components. (Source: Wikipedia)