Editing Reference (computer science) (section)

{{Short description|Data type which allows a program to indirectly access a particular value in memory}}
{{About|the general concept in computing|the more specific concept in C++|Reference (C++)}}
{{More citations needed|date=November 2010}}

In [[computer programming]], a '''reference''' is a value that enables a program to indirectly access a particular [[datum]], such as a [[variable (computer science)|variable]]'s value or a [[record (computer science)|record]], in the [[computer]]'s [[memory (computing)|memory]] or in some other [[Data storage device|storage device]].  The reference is said to '''refer''' to the datum, and accessing the datum is called '''[[Dereference operator|dereferencing]]''' the reference. A reference is distinct from the datum itself.

A reference is an [[abstract data type]] and may be implemented in many ways. Typically, a reference refers to data stored in memory on a given system, and its internal value is the [[memory address]] of the data, i.e. a reference is implemented as a [[Pointer (computer programming)|pointer]]. For this reason a reference is often said to "point to" the data. Other implementations include an offset (difference) between the datum's address and some fixed "base" address, an [[array index|index]], or [[identifier]] used in a [[lookup]] operation into an [[Array data structure|array]] or [[table (database)|table]], an operating system [[Handle (computing)|handle]], a [[physical address]] on a storage device, or a network address such as a [[URL]].