A "query" is a request for information from a database. The most common type of query is textual, such as the keywords people type when using a web search engine.

A "graphical query" is a request for information that takes the form of an image. Some systems return images that are similar to a sketched shape. Other systems let people specify colors or textures to use as graphical queries.

On October 19, 1999, Ken Church, Jonathan Helfman, and David Lewis receivedUS Patent 5,970,484 "Method for retrieving texts which are similar to a sample text," to protect a type of graphical query for use with a fax-based information retrieval system, which was prototyped by Helfman for AT&T Bell Labs in 1996 under the internal name "fax-a-query". The patent was later assigned to Lucent Technologies. Here is the abstract of the patent:

An information retrieval method wherein users may submit a query via a graphical bitmapping technique. The user provides an information retrieval system with a bitmap of a printed, written, or graphical query by either scanning the query with a graphical scanner, or employing a standard facsimile transmission machine. The information retrieval system then performs an optical image/character recognition process upon the received bitmap to determine the content of the query, information is then retrieved based upon the recognized characters and images. In a particular method of the invention, the user is provided with a bitmap of the retrieved information.