Java, developed by James Gosling at Sun Microsystems in 1995, is a platform-independent programming language that allows programs to run on any machine with a Java Virtual Machine (JVM). Its key features include portability, memory management through an automatic garbage collector, and the ability to run Java bytecode on various platforms, enhancing efficiency despite some slower speeds in execution. The language's object-oriented nature and capabilities in threading and networking contribute to its ongoing popularity in application development.