Explain 'Pass by Value' vs 'Pass by Reference'.

Explain 'Pass by Value' vs 'Pass by Reference'.

Approach: Compare copying data vs copying memory address.

Pass by value sends a copy of the data; changes inside the function do not affect the original. Pass by reference sends a reference to the data; changes affect the original.

Follow-up: How does Python handle argument passing?

Key concepts: pointers, stack, function arguments.