An object-oriented, distributed, interpreted, architecture-neutral, portable, multithreaded, dynamic, buzzword-compliant, general-purpose programming language developed by Sun Microsystems in the early 1990s (initially for set-top television controllers) and released to the public in 1995.
Java first became popular as the earliest portable dynamic client-side content for the web in the form of platform-independent Java applets. In the late 1990s and into the 2000s it also became very popular on the server side, where an entire set of APIs defines the J2EE.
Java is syntactially similar to C++ without user-definable operator overloading, (though it does have method overloading), without multiple inheritance and extensive automatic coercions. It has automatic garbage collection. Java extends C++'s object-oriented facilities with those of Objective C for dynamic method resolution.
Whereas programs in C++ and similar languages are compiled and linked to platform-specific binary executables, Java programs are typically compiled to portable architecture-neutral bytecode ".class" files, which are run using a Java Virtual Machine. The JVM is also called an interpreter, though it is more correct to say that it uses Just-In-Time Compilation to convert the bytecode into native machine code, yielding greater efficiency than most interpreted languages, rivalling C++ for many long-running, non-GUI applications. The run-time system is typically written in POSIX-compliant ANSI C or C++. Some implementations allow Java class files to be translated into native machine code during or after compilation.
The Java compiler and linker both enforce strong type checking - procedures must be explicitly typed. Java aids in the creation of virus-free, tamper-free systems with authentication based on public-key encryption.
Java has an extensive library of routines for all kinds of programming tasks, rivalling that of other languages. For example, the java.net package supports TCP/IP protocols like HTTP and FTP. Java applications can access objects across the Internet via URLs almost as easily as on the local file system. There are also capabilities for several types of distributed applications.
The Java GUI libraries provide portable interfaces. For example, there is an abstract Window class with implementations for Unix, Microsoft Windows and the Macintosh. The java.awt and javax.swing classes can be used either in web-based Applets or in client-side applications or desktop applications.