6. A system comprising: one or more computers and one or more storage devices storing instructions that are operable, when executed by the one or more computers, to cause the one or more computers to perform operations comprising: receiving, by a search system, (i) a pixel map corresponding to one or more characters that have been drawn on a display of a client device and (ii) data identifying one or more other characters that were previously recognized by the search system using one or more other pixel maps; recognizing, by the search system, the one or more characters that correspond to the pixel map based on the received pixel map and the one or more other characters; formulating, by the search system, a search that includes the one or more characters and the one or more other characters as a query term; and communicating, by the search system, (i) one or more search results for the search, (ii) data identifying the one or more characters that correspond to the received pixel map, and (iii) data identifying the one or more other characters to the client device that were previously recognized by the search system using the one or more other pixel maps.
6. A system comprising: one or more computers and one or more storage devices storing instructions that are operable, when executed by the one or more computers, to cause the one or more computers to perform operations comprising: receiving, by a search system, (i) a pixel map corresponding to one or more characters that have been drawn on a display of a client device and (ii) data identifying one or more other characters that were previously recognized by the search system using one or more other pixel maps; recognizing, by the search system, the one or more characters that correspond to the pixel map based on the received pixel map and the one or more other characters; formulating, by the search system, a search that includes the one or more characters and the one or more other characters as a query term; and communicating, by the search system, (i) one or more search results for the search, (ii) data identifying the one or more characters that correspond to the received pixel map, and (iii) data identifying the one or more other characters to the client device that were previously recognized by the search system using the one or more other pixel maps. 10. The system of claim 6 , wherein the search comprises an image search.