J2 is a term that can refer to various concepts, but it is often associated with the Java 2 Platform, which is a set of core libraries and tools for developing applications in the Java programming language. Released in 1998, it introduced significant improvements over its predecessor, including the Swing graphical user interface toolkit and the Java 2 Runtime Environment. In a different context, J2 can also refer to the J2EE (Java 2 Platform, Enterprise Edition), which is designed for building large-scale, multi-tiered, distributed applications. It provides a robust framework for developing enterprise-level applications, including features like servlets, JavaServer Pages (JSP), and Enterprise JavaBeans (EJB).