What do you understand by Java virtual machine?

What is the difference between JDK, JRE, and JVM?

How many types of memory areas are allocated by JVM?

What is JIT compiler?

What is the platform?

What are the main differences between the Java platform and other platforms?

What gives Java its 'write once and run anywhere' nature?

What is classloader?

Is Empty .java file name a valid source file name?

Is delete, next, main, exit or null keyword in java?

If I don't provide any arguments on the command line, then what will the value stored in the String array passed into the main() method, empty or NULL?