24. The volatile or non-volatile computer-readable storage medium of claim 18 , wherein the one or more sequences of instructions, when executed by the one or more processors, further cause the one or more processors to perform: categorizing a query by the one or more computing devices performing: locating a particular node in a set of nodes of a graph, the particular node representing a particular term that matches the query; using the graph to locate the third node by traversing the graph away from the particular node; categorizing the query as in the category based at least in part on the stored information that indicates the third term is in the category.
24. The volatile or non-volatile computer-readable storage medium of claim 18 , wherein the one or more sequences of instructions, when executed by the one or more processors, further cause the one or more processors to perform: categorizing a query by the one or more computing devices performing: locating a particular node in a set of nodes of a graph, the particular node representing a particular term that matches the query; using the graph to locate the third node by traversing the graph away from the particular node; categorizing the query as in the category based at least in part on the stored information that indicates the third term is in the category. 25. The volatile or non-volatile computer-readable storage medium of claim 24 , wherein the one or more sequences of instructions, when executed by the one or more processors, further cause the one or more processors to perform: receiving, from the user, a selection of a set of selected terms in the category; and storing a second information that indicates that the query is associated with the set of selected terms.