A pointer in programming languages like C++ is a variable that stores the address of another variable. It can be reassigned to point to different addresses. A reference, on the other hand, is an alias for another variable and once set, it cannot be made to reference another variable.
Pointers can be assigned null, meaning they point to nothing. This feature makes them useful for checking if they have valid data. References must always refer to an object; they cannot be null. This ensures that a reference always points to a valid memory location.
With pointers, direct manipulation of memory addresses is possible. This includes arithmetic operations on addresses. References do not allow such direct interaction with memory addresses, making them safer but less flexible.
A pointer requires explicit dereferencing to access the target object’s value. References implicitly refer to the value of the object they are referencing, making them easier to use but hiding the underlying complexity.
Pointers are often used in complex data structures, dynamic memory allocation, and low-level system programming due to their flexibility. References are used when a variable must be passed by reference to functions or when an alias for a variable is needed, ensuring more straightforward and safer code.
