The invention relates to an improved keyboard and keyboard driver for facilitating a reduction in the number of key presses required to create or delete a given data string (i.e. mnemonics, abbreviations, words, sentences, paragraphs etc.). The keyboard includes an array of keys having multi-character indicia and an interface system comprising data storage means; data processing means; and data display means, wherein the data processing means reduces key presses by filtering data stored within the data storage means by initial character, as determined by the character or characters ascribed to a data input key initially pressed by a user, and prioritizing the filtered data in real-time according to user-configurable prioritization parameters (using qualitative and/or quantitative information relating to each data string stored within the storage means). The invention also provides improved calculator functionality and function-lock keys. Taken together, the keyboard and keyboard driver of the invention (which may be implemented in isolation or together) promotes ease of use, reduced user-interactivity, elevated efficiency and thus enhanced productivity that in turn yields improved accuracy and flexibility.