What is the difference between pointers and references, and why?

Question

Accepted Answer

Pointers are variables that store memory addresses; references are aliases for existing variables.

Pointers can be reassigned to point to different variables, e.g., int* ptr = &var1; ptr = &var2;
References must be initialized when declared and cannot be changed to refer to another variable, e.g., int& ref = var1;
Pointers can be null, meaning they point to no valid memory, while references must always refer to a valid object.
Pointers require dereferencing (using *) to access the value they point to, while references can be used directly.

Accepted Answer

References are used to refer an existing variable in another name whereas pointers are used to store address of variable.

References cannot have a null value assigned but pointer can.

A reference variable can be referenced by pass by value whereas a pointer can be referenced by pass by reference.