11. A non-transitory computer readable medium storing instructions that when executed by one or more computers cause the one or more computers to perform operations for providing query parameters to a search engine, comprising: receiving data specifying two or more locations of a graphical user interface that were included in a user selection area; determining, based on the received data, that a first portion of text is included in the user selection area; creating a textual search query based at least in part on the first portion of text; identifying a second portion of text that is presented in the graphical user interface, but is not included in the user selection area; modifying the textual search query based at least in part on the second portion of text, wherein the modifying comprises: including, in the textual search query, a word that differs from words included in the first and second portions of text and describes a context of the second portion of text; and submitting, by one or more computers, the modified textual search query to the search engine.
11. A non-transitory computer readable medium storing instructions that when executed by one or more computers cause the one or more computers to perform operations for providing query parameters to a search engine, comprising: receiving data specifying two or more locations of a graphical user interface that were included in a user selection area; determining, based on the received data, that a first portion of text is included in the user selection area; creating a textual search query based at least in part on the first portion of text; identifying a second portion of text that is presented in the graphical user interface, but is not included in the user selection area; modifying the textual search query based at least in part on the second portion of text, wherein the modifying comprises: including, in the textual search query, a word that differs from words included in the first and second portions of text and describes a context of the second portion of text; and submitting, by one or more computers, the modified textual search query to the search engine. 15. The computer readable medium of claim 11 , wherein the receiving the data specifying the two or more locations of the graphical user interface that were included in the user selection area comprises receiving input specifying that a computer mouse performed a click-and-drag operation.