Abstract: An ambiguity resolver having an input for receiving a data string entered using an ambiguous keyboard, a comparator for comparing the data string to be searched against a plurality of prestored words to find at least one closest match to the data string, and an output for outputting a comparison result. An ambiguous keyboard is one in which more than one character is mapped to a single key, a particular example being a telephone keypad used for entering all the alphanumeric characters.