What is the Stack data structure in JVM and how does it work?

In JVM, the data structure Stack is a call stack, which is used to store information about methods that are currently executing. Each thread in the JVM has its own stack.

When a method is called, a frame (stack frame) is pushed onto the stack, containing local variables, operands, and return information. After the method completes, the frame is removed from the stack.

The stack operates on the LIFO (Last In, First Out) principle: the last called method finishes first. This ensures the correct order of returning from method calls.

Example: when method A is called, which calls method B, the stack will first contain the frame for A, then for B. After B finishes, its frame is removed, and control returns to A.