Differentiate between stack and heap allocation

Stack:

• Stored in Computer RAM like the heap.
• Variables created on the stack will go out of scope and automatically deallocate.
• Much faster to allocate in comparison to variables on the heap. • Implemented with an actual stack data structure.
• Stores local data, return addresses, used for parameter passing
• Can have a stack overflow when too much of the stack is used. (mostly from infinite (or too much) recursion, very large allocations)
• Data created on the stack can be used without pointers.
• You would use the stack if you know exactly how much data you need to allocate before compile time and it is not too big.
• Usually has a maximum size already determined when your program starts.

Heap:

• Stored in computer RAM like the stack.
• Variables on the heap must be destroyed manually and never fall out of scope. The data is freed with delete, delete[ ] or free
• Slower to allocate in comparison to variables on the stack.
• Used on demand to allocate a block of data for use by the program.
• Can have fragmentation when there are a lot of allocations and deallocations
• In C++ data created on the heap will be pointed to by pointers and allocated with new or malloc
• Can have allocation failures if too big of a buffer is requested to be allocated.
• You would use the heap if you don’t know exactly how much data you will need at runtime or if you need to allocate a lot of data.
• Responsible for memory leaks.