43. A computer apparatus for automatically processing a document containing text represented by characters, comprising: input means for automatically inputting a document into a memory of the computer apparatus to produce document data; a processor coupled to said memory and including: frequency determining means, receiving said document data from said memory, for automatically determining a frequency of occurrence of expressions in the document not contained in a stop list and having at least a first predetermined level of complexity, said frequency determining means outputting expression frequency data, said stop list stored in said memory; seed list defining means, receiving said expression frequency data from said frequency determining means, for automatically defining a seed list comprised of a second predetermined number of the most frequently occurring expressions in the document, said seed list stored in said memory; identifying means for automatically identifying portions of the document data containing at least two members of said seed list; summarizing means for automatically forming a summary by combining said portions identified by said identifying means, said summary stored in said memory; length determining means for automatically determining whether a length of said summary is not greater than a predetermined length; and control means for automatically outputting said summary as a document summary when said length determining means determines said summary to be not greater than said predetermined length, otherwise automatically inputting said summary as a document to said input means, adding members of said seed list to said stop list, and reducing said first predetermined level of complexity so that said document data is iteratively processed until a document summary is produced having a length not greater than said predetermined length.
53. The apparatus of claim 43, wherein said summarizing means forms said summary by extracting said portions from said document and constructing said summary from said extracted portions while maintaining said extracted portions in a same order in said summary as in the document.