The company currently provides websites with CAPTCHAs (completely automated public turing test to tell computers and humans apart) -- which is a technical description of those random letters internet users are required to type into a box when registering on a website -- an irksome but necessary part of people's online lives.
The company provides its service for more than 100,000 websites to protect them from spam and fraud.
Google said the acquisition, announced on its blog, will enable the search giant to apply the technology to its books and newspaper scanning process. It will also integrate the technology on other Google products to shore up its fraud and spam protection.
Google said: "ReCaptcha's unique technology improves the process that converts scanned images into plain text, known as Optical Character Recognition (OCR)...Having the text version of documents is important because plain text can be searched, easily rendered on mobile devices and displayed to visually impaired users.
"Improving the availability and accessibility of all the information on the Internet is really important to us, so we're looking forward to advancing this technology with the reCAPTCHA team."