1) What is difference between JDK,JRE and JVM? JVM JVM is an acronym for Java Virtual Machine, it is an abstract machine which provides the runtime environment in which java bytecode can be executed. It is a specification. JVMs are available for many hardware and software platforms (so JVM is platform dependent). JRE JRE stands for Java Runtime Environment. It is the implementation of JVM. JDK JDK is an acronym for Java Development Kit. It physically exists. It contains JRE + development tools. more details... 2) How many types of memory areas are allocated by JVM? Many types: Class(Method) Area Heap Stack Program Counter Register Native Method Stack more details... 3) What is JIT compiler? Just-In-Time(JIT) compiler: It is used to improve the performance. JIT compiles parts of the byte code that have similar functionality at the same time, and hence reduces the amount of time needed for compilation.Here the term “compiler” refers to a tra
