What do you understand by java virtual machine?

Answer 1

JVM is a virtual system unlike the physical system you have. It is responsible for converting the java bytecode to machine code that can be understood by the system.

JVM itself is not a compiler but it has a Just In Time (JIT) compiler which converts a big block of bytecode to machine code. The JIT compiler makes the language faster because a method which already has been interpreted is converted to a native code and every time that method is called in the program, that native code is executed directly.

Answer 2

The thing that translates and executes the bytecode that the compiler previously generated from your source code.