Java is an object-oriented, platform-independent programming language that can be used to develop a wide range of applications. It has features like being simple, secure, portable and supporting multithreading. Java is commonly used to build web applications, mobile apps, and enterprise software due to its ability to write once and run anywhere. It was originally developed in the 1990s by James Gosling at Sun Microsystems with a goal of platform independence and has become one of the most popular programming languages.