Java is a statically typed, class-based programming language and runtime platform designed around portability, safety, tooling, and a large standard library. Java source is normally compiled into JVM bytecode rather than directly into one operating system's machine code. A compatible Java Virtual Machine then executes that bytecode.

The important distinction is between the language and the platform. The language defines syntax and semantics such as classes, interfaces, generics, exceptions, and pattern matching. The platform supplies the JVM, standard libraries, command-line tools, garbage collection, monitoring facilities, and a mature ecosystem.

Java is widely used for backend services, enterprise systems, data processing, financial software, developer tools, and high-throughput server applications.

public class HelloJava {
    public static void main(String[] args) {
        System.out.println("Hello, Java!");
    }
}