30. A computer implemented method of responding to a search query made to a fact repository, performed at a computer system having one or more processors and memory storing one or more programs for execution by the one or more processors, the method comprising: receiving the search query; and in response to receiving the search query, returning annotations corresponding to the search query from annotations for a plurality of snippets of facts in the fact repository, wherein the fact repository includes a plurality of facts associated with objects, wherein a respective fact in the fact repository includes a respective attribute and a respective value, wherein the respective value is a text string, and wherein the plurality of facts are extracted from a plurality of documents, wherein an annotation includes additional information about a fact, and wherein a value of the annotation is indexed to a substring of a fact's value.
30. A computer implemented method of responding to a search query made to a fact repository, performed at a computer system having one or more processors and memory storing one or more programs for execution by the one or more processors, the method comprising: receiving the search query; and in response to receiving the search query, returning annotations corresponding to the search query from annotations for a plurality of snippets of facts in the fact repository, wherein the fact repository includes a plurality of facts associated with objects, wherein a respective fact in the fact repository includes a respective attribute and a respective value, wherein the respective value is a text string, and wherein the plurality of facts are extracted from a plurality of documents, wherein an annotation includes additional information about a fact, and wherein a value of the annotation is indexed to a substring of a fact's value. 31. The method of claim 30 , wherein the facts are extracted from the plurality of documents without user interaction.