The Java Runtime Environment (JRE) is a software package that Java programs require in order to run successfully. It is one of the three Java platform components that are required for any Java program to run successfully, the other two being the Java Development Kit (JDK) and Java Virtual Machine (JVM) . The JRE is a software layer that provides a virtual machine and a set of libraries for executing Java programs. It acts as a translator and facilitator, providing all the resources so that once you write Java software, it runs on any operating system without further modifications. The JRE is responsible for managing the execution of Java code and providing a consistent runtime environment across different platforms including but not limited to: Windows, Linux, macOS, Solaris and various mobile operating systems such as Android and iOS.
The JRE is made up of several components, including the Java Virtual Machine (JVM), Java class libraries, and the Java class loader. The JVM is responsible for executing Java programs and is the component that actually runs the bytecode generated by the Java compiler. The Java class loader loads compiled Java code into memory and connects the code to the appropriate Java class libraries. The Java class libraries provide a set of pre-written code that Java programs can use to perform common tasks, such as reading and writing files, networking, and user interface development.
The JRE is important because it allows Java programs to run on virtually any operating system without modification. It also provides value-added services, such as automatic memory management, which ensures that programmers dont have to manually control the allocation and reallocation of memory. The JRE contains several deployment tools that make it easy to package and distribute Java applications, such as Java Web Start and Java Applets.
