What will happen in memory, when we run a java program?

Memory architecture of a java program:

Once you compile and execute your java program, it will be loaded into memory (RAM). Note: Remember if you want to run a program, it should be loaded into RAM. Once it is loaded into memory, it will become a process. Every process in memory will be allocated many segments. Out of which 4 segments are very important. So every java program, once executed, it will have 4 segments in memory. 1.Data segment (stores static variables) 2.Code segment (stores your code) 3.Stack (stores local variables) 4.Heap (stores objects, and instance variables) Below diagram shows the pictorial representation of a java program's memory architecture.
As long as your program is in hard disk it is called as program or application. Once it is loaded into memory, it is called as a process.