JVM (Java Virtual Machine)

When we compile a Java file, output is not an .exe but it’s a .class file. This .class is known as Java byte code, It has the Java byte codes which can be understood by JVM. Java Virtual Machine interprets the byte code into the machine code and execute it. It is responsible for all the things like garbage collection, array bounds checking, etc… JVM is a cornerstone of the write-once run-anywhere value of Java programs.

Note: JVM is platform dependent but it makes the Java platform independent.

The Java Virtual Machine provides a platform-independent way of executing code; programmers can concentrate on writing software, without having to be concerned with how or where it will run.

JIT (Just-in-time Compiler):

JIT also known as dynamic translation. JIT is the part of the Java Virtual Machine (JVM) that helps to speed up the execution time. Parts of the byte code that have similar functionality at the same time complied by JIT and saves time needed for compilation. It translates the instruction set of a Java virtual machine (JVM) to the instruction set of a specific CPU.

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