Java Card refers to a technology that allows Java-dd applications (applets) to be run securely on smart cards and similar small memory footprint devices.
Java Card is the tiniest of Java targeted for embedded devices, typically smart cards. Java Card gives developers the ability to program the device and make them application specific. It is widely used in SIM cards (used in GSM mobile phones) and/or NFC secure elements, ATM cards (containing an EMV chip), and machine readable travel documents.
The first Java Card was introduced in 1996 by Schlumberger's card division which later merged with Gemplus to form Gemalto. Java Card products are based on the Java Card specifications developed by Sun Microsystems (which is now Oracle Corporation). Many Java Card products rely on the GlobalPlatform specifications for the secure management of applications on the card (download, installation, personalization, deletion). GlobalPlatform was created to manage OpenPlatform, which was an initiative of Visa Inc.
The main design goals of Java Card are portability and security. Although the Java classes are initially compiled using the Java SE compiler there are many restrictions on Java Card. For instance, Java Card Classic does not support String and integer support is optional; object instances are created in persistent memory instead of RAM by default. Java Card has some features that are not present in J2SE as well: application isolation through the so-called applet firewall and a transaction mechanism.
