In C++, `nullptr` is a keyword introduced in C++11 that represents a null pointer constant. It is used to indicate that a pointer does not point to any valid memory location. Unlike the older `NULL`, which is typically defined as zero, `nullptr` has a specific type, making it safer and more type-safe when used in function overloading and pointer comparisons. Using `nullptr` helps prevent errors that can arise from using uninitialized pointers. It improves code readability and clarity, allowing developers to express the intent of a null pointer more explicitly. Overall, `nullptr` is a modern and preferred way to handle null pointers in C++.