• Heap space : JVM allocates some memory from OS, object is created from Heap and returned to the heap at the end of it's life cycle.
    • JVM reclaim heap space from the expired objects.
    • In Servers,  default JVM maximum heap space is 1G /4GB of physical memory on a 32 bit and in 64 bit JVM its 32G / 128GB of physical memory. RAM
    • Heap dump : Java Heap dump is a snapshot of Java Heap Memory at a given time
  • Stack : local variables are stored
follow up : http://www.javatpoint.com/internal-details-of-jvm