1. A method of detecting the inclusion of records in an input string of words comprising: a. pre-processing the records such that at least a portion of the records are represented by a string; said string comprising a plurality of sections wherein each of the said sections (chunks) comprises a pre-defined number of elementary words, in the manner that when a chunk is the first chunk in the chunk representation of a record a “Begin of Record” attribute is assigned to the said chunk and when a chunk is the last chunk in the chunk representation of a record, an “End of Record” attribute is assigned to it; b. searching said string in the manner that the input string is divided into a plurality of chunks and each of said chunks is searched in the records so that if a searched chunk is found to be present in at least one record, a Partial Match Flag is set according to a logic calculation; and, c. calculating an Incremental Hash Function (IHF) for each input chunk; characterized by that whenever a chunk from the input string is found to be in at least one of the records, and the said chunk is associated with an End of Record and the Partial Match is set for this chunk (End of Record chunk), the difference values between the value of the IHF at that “End of Record” chunk and the value of the IHF at each of the previous chunks of the said string, to which a “Begin of Record” is associated (Begin of Record Chunk), is calculated and compared with all pre-recorded values ΔI, calculated during the pre-processing for each record having the said End of Record chunk as last chunk, and associated to the said End of Record chunk; and further characterized by that whenever any of the said pre-recorded value ΔI coincides with at least one of the said difference values, a “probable match” is set, indicating a very high probability for an exact match.