What is "pointer"

A pointer is a type of data that "points to" another value stored in memory using its address. Pointers have a variety of performance benefits in repetitive operations. For example, the copy of a pointer is "cheaper" than copying the value it points to because only the address should be copied. Pointers are an important concept in many high-level programming languages, including C and C++. A Wikipedia page for pointers has an introduction on the concept.