13.1. Introduction to Java Card
Java Card technology enables programs written in the Java programming language to run in smart cards and other memory-constrained devices. Java Card technology is widely deployed in many industry sectors, including mobile cellular handsets, health care identity cards, and financial services. Java Card technology consists of three components:
The Java Card Virtual Machine (JCVM) specification  defines a subset of the Java programming language and virtual machine specifications that is suitable for smart card applications.
The Java Card Runtime Environment (JCRE) specification  describes Java Card runtime environment behavior: memory management, application management, security enforcement, and other runtime ...