1. A pattern matching and pattern recognition system for performing pattern matching and pattern recognition of input data, comprising: an associative memory core which includes registration means for selectively registering a plurality of reference words based on a second distance index that allows coding of a first distance index, simultaneously and parallelly performs bit comparison and word weighting comparison for all said plurality of reference words with respect to the input word in a predetermined clock cycle on the basis of the input word, and searches for a word exhibiting the largest similarity (minimum distance) with respect to the input word as a winner; retrieved word extraction means for extracting a retrieved word having a predetermined number of bits from the input data in the clock cycle; first coding means for coding the retrieved word, extracted by the retrieved word extraction means, with the second distance index, and outputting the word to the associative memory core; analysis means for analyzing an output result from the associative memory core in a previous clock cycle, and if a search result includes a plurality of winners, determining one winner on the basis of a specific priority criterion; and second coding means for coding an index (address) indicating a location of a row of the winner determined by the analysis means and a distance based on the first distance index between input data and the winner, and outputting the index and the distance, wherein the retrieved word extraction means and the first coding means are executed in a first pipeline stage, winner search by the associative memory core is executed in a second pipeline stage, and the analysis means and the second coding means are executed in a third pipeline stage.