"Utkarsh", The Java Ranch has thousands of visitors every week, many with surprisingly similar names. To avoid confusion we have a naming convention, described at http://www.javaranch.com/name.jsp . We require names to have at least two words, separated by a space, and strongly recommend that you use your full real name. Please choose a new name which meets the requirements. Thanks.
The compiler converts source into bytecode. The JVM or JRE interprets the bytecode into machine language to run. At execution time objects are created in RAM (actually in the stack and heap areas of RAM). The JVM (Java Virtual Machine) is actually a set of specifications that Sun puts out for makers of browsers and embedded chips etc. to follow when creating their JVMs for their products. When you run an applet or servlet it is running in a JVM. The JRE (Java Runtime Environment) is the equivalent of a JVM but for running applications outside of a browser (like from the DOS prompt). It contains the Java Foundation Classes for the release of Java that it implements. A JIT (Just In Time Compiler) is a tool to increase the performance of Java Applications. If the "interpreting" of the code is slowing things down, then you can use a JIT to actually compile the JAVA code on the fly to a machine specific version, which speeds things up. Check out http://www.javaranch.com/ubb/Forum1/HTML/000791.html
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