Tesseract OCR free open source software (!)

Tesseract (software) - Wikipedia, the free encyclopedia:
Tesseract is an optical character recognition engine for various operating systems.[2] It is free software, released under the Apache License, Version 2.0,[1][3][4] and development has been sponsored by Google since 2006.[5]Tesseract is considered one of the most accurate open source OCR engines currently available.[4][6]

tesseract-ocr - An OCR Engine that was developed at HP Labs between 1985 and 1995... and now at Google. - Google Project Hosting

Comparison of optical character recognition software - Wikipedia, the free encyclopedia

Microsoft Office Document Imaging - Wikipedia, the free encyclopedia
(not included in Office 2010)

charlesw/tesseract · GitHub
A .Net wrapper for tesseract-ocr