1. The Program Stack

• A stack is an area of memory for storing data temporarily.

• Unlike other segments that store data starting from low memory, the stack stores data starting from high memory.

• The data is said to be pushed onto, and popped from the top of the stack.

• The stack gets its name from its similarity to the spring-loaded plate holders in cafeterias: you add and remove plates from only the top of the stack.

• To retrieve the third plate, you must remove (pop) the first two plates.

• Stacks are often referred to as LIFO buffers, from their last-in-first-out operation.

• A program continually uses its stack to temporarily store and preserve return addresses, procedure arguments, memory data, flags, and registers.