10. A non-transitory memory device storing instructions, the instructions comprising: one or more instructions which, when executed by at least one processor, cause the at least one processor to select a plurality of documents, where each document, of the plurality of documents, includes a hyperlink to a target document; one or more instructions which, when executed by the at least one processor, cause the at least one processor to select, for each document of the plurality of documents, text from the document, where the selected text from the document is included in a paragraph in the document that includes the hyperlink, the selected text including less than an entire content of the document; one or more instructions which, when executed by the at least one processor, cause the at least one processor to incorporate, for each document of the plurality of documents, text from a header of the document into the selected text; one or more instructions which, when executed by the at least one processor, cause the at least one processor to associate the selected texts including the incorporated texts from the headers, with the target document; one or more instructions which, when executed by the at least one processor, cause the at least one processor to filter the selected texts with the incorporated text from the headers, based on predetermined criteria to select one or more of the selected texts with the incorporated text from the headers, as descriptive text that describes the target document; one or more instructions which, when executed by the at least one processor, cause the at least one processor to rank the descriptive text based on a linking structure of each document, of the plurality of documents, where the linking structure, for each document, of the plurality of documents, is determined by a probability distribution that represents a likelihood that a user, randomly clicking on links, will arrive at the document; one or more instructions which, when executed by the at least one processor, cause the at least one processor to select one of the descriptive text based on the ranking one or more instructions which, when executed by the at least one processor, cause the at least one processor to store, in an entry, of a plurality of entries in an index, information associating the target document with a corresponding term appearing in the target document; and one or more instructions which, when executed by the at least one processor, cause the at least one processor to store, in another entry, of the plurality of entries in the index, information associating the target document with a descriptive text term, the descriptive text term appearing in the selected descriptive text and not appearing in the one or more instructions which, when executed by the at least one processor, cause the at least one processor to receive information identifying the target document as relevant to a search query based on the descriptive text term, the received information being generated based on information included in the index; and one or more instructions which, when executed by the at least one processor, cause the at least one processor to provide information regarding the target document and the selected descriptive text based on receiving the information identifying the target document as relevant to the search query.
11. The memory device of claim 10 , where the predetermined criteria comprise at least one of a length of the selected texts and the texts from the headers, punctuation present in the selected texts and the texts from the headers, verbs present in the selected texts and the texts from the headers, positions of verbs present in the selected texts and the texts from the headers, and adjectives present in the selected texts and the texts from the headers.