What is the difference between pointers and references in C++?

Pointers store memory addresses, can be null, can be reassigned, require dereferencing (*) to access value, use -> for member access. References are aliases to existing variables, cannot be null, must be initialized, cannot be reassigned, access value directly. Pointers allow arithmetic and dynamic memory; references are safer and cleaner. Use references for function parameters (avoid copying, allow modification). Use pointers when null is valid, reassignment needed, or for dynamic allocation. References are preferred when possible for safety.