OMR-Code – Optical Mark Recognition
Optical mark recognition (OMR) is a technique allowing computer-assisted identification of marks on paper, similarly to text recognition (optical character recognition or OCR).
Optical mark recognition is often used to automatically evaluate forms such as multiple choice tests or voting slips. Modern enveloping machines also require OMR codes on letters to provide instructions.
As well as conventional optical mark recognition codes (one-dimensional codes or control characters, which are generally found between the punch holes in a document), barcodes and DataMatrix codes are also used.