Providing category information includes: receiving a plurality of search key word sets that were previously input by a plurality of users; obtaining category information corresponding to the plurality of search key word sets; segmenting each of the plurality of search key word sets into search key word units; combining the search key word units into a plurality of search key word unit groups that correspond to a plurality of stages; based at least in part on the category information, determining category information that specifically corresponds to the plurality of search key word unit groups; and based at least in part on category information, establishing a plurality of search key word tables corresponding to the plurality of stages.