Java is a versatile, object-oriented programming language used for building web applications, mobile apps, and enterprise software. It is known for its platform independence, security, and scalability. With an Online Java Compiler, developers can write, test, and execute Java programs instantly without the need for installation. This makes learning and practicing Java more convenient for beginners and professionals. Whether for backend development, Android applications, or cloud computing, Java remains one of the most popular programming languages worldwide.