A method of addressing a location by virtue of its data content rather than by its physical location. An access is made by specifying something about the contents of the desired location rather than by using a normal address. An associative memory (or content-addressable memory) provides a search mechanism to match on the whole or on partial memory contents for a word that satisfies the match. In some applications it may be permissible for more than one word to be found. The desired data will be in close association or proximity, possibly as an additional field of the retrieved word. An associative processor exploits the parallel-access facility of associative memory to achieve a form of parallel processing.