JAVA

Java consists of

J2SE
Core/Desktop
J2EE
Enterprise/Server
J2ME
Mobile/Wireless
Java Card
Java Web Services
XML
Other Java Technologies

APIs

JDBC

JTA (Java Transaction API)

JNDI (Java Naming and Directory Interface)

See also here.

JMS (Java Message Service)

JavaMail

Java IDL

The API for calling CORBA services.

Java, the language

Go here

Not yet categorized...

applets.

javac