OCR

Stands for "Optical Character Recognition." Simply put, this is what allows you to scan that paper you printed out, but lost on your hard drive, back into your computer. When a page of text is scanned into a computer, at first, all the computer sees is a bunch graphical bits. In other words, it has no idea that there's text on the page, much less what the text says. However, an OCR program can convert the characters on the page into a text document the computer can read. It isn't always a perfect translation, but the newer OCR programs are very accurate. The better ones can even keep the formatting of the document in the translation.