eBay explained in the patent filing:
“Information retrieval relates to the searching of information stored on computing systems, such as searches for web pages, items for sale, documents, and images. To locate particular information, a user specifies a query about the information of interest and a search engine, for example, uses this query in the search. For example, online shopping and auction websites provide a number of publishing, listing, and price-setting mechanisms whereby a seller may list (or publish information concerning) items for sale. A buyer can express interest in or indicate a desire to purchase such items by, for example, submitting a query to the website for use in a search of the requested items.
“The accurate matching of a query to relevant items is currently a major technical challenge in the field of information retrieval. An example of such a challenge is that item descriptions (e.g., title) tend to be short and such descriptions may be uniquely defined by the sellers. The buyers seeking to purchase the items might use a different vocabulary from the vocabulary used by the sellers to describe the items. As an example, an item identified in the title as a “garnet” does not match a query “January birthstone” submitted by a buyer, although garnet s known as the birthstone for January. In another example, an item identified in the title as “Martin guitar” does not match the query “acoustic guitar” submitted by a buyer, although the Martin guitar is a type of an acoustic guitar. As a result, for example, online shopping and auction websites that use a conventional search engine to locate items may not effectively connect the buyers to the sellers.”