# 7.4: Void Data Type

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## General Discussion

The void data type has no values and no operations. It's a data type that represents the lack of a data type.

 C++ Reserved Word void Represent Nothing Size N/A or None Normal Signage N/A Domain (Values Allowed) None

This data type was added in the transition from "C" to "C++". In "C" by default a function returned an integer data type. Some functions don't return a value of any kind. Thus, the need to have a data type that indicates nothing is being returned. The void data type is mainly used in the definition and prototyping of functions to indicate that either nothing is being passed in and/or nothing is being passed out.

## Definitions

Void Data Type
A data type that has no values or operators and is used to represent nothing.

This page titled 7.4: Void Data Type is shared under a CC BY license and was authored, remixed, and/or curated by Kenneth Leroy Busbee (OpenStax CNX) .