A user programmable smart card interface system is disclosed having a smart card (10) and a reader/writer (1) which is able to read data from, and write data into, an electronic memory (19) carried by the card. A user terminal (100) having processing capacity can be used by a user to write customised data into the electronic memory (19). The user is then able to utilise his own data to control a data controlled equipment (120) as the user desires. A storage apparatus (1000) for smart cards and smart cards (501) with a tactile operating surface arc also disclosed.