Modern society would like to replace paper by electronic data carriers and mechanical processes by electronic processes. Smartcards offer one means to this end in the form of a personal mobile security device. Personal data can be stored in a mobile personal environment instead of in a central database, and processor smartcards additionally provide a sort of pocket PC that can perform security functions at a higher level of security than an ordinary PC. Interoperability of different smartcards with different smartcard readers and data terminals is very important; therefore, standards exist for the structure of data objects on the card and for coding the commands sent to the card. Biometric user-authentication is becoming increasingly important for smartcards as an alternative to the previously used PIN or password authentication. Additional convenience for the user can be provided by contactless cards.