# What is a Data type?

* A Data Type is a categorization of data. A Data Type in a variable defines how the variable's value will be interpreted and processed.
* Simple data types are String, Boolean, Integer, Numerical, Character, GUID, Timestamp, and DateTime.

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* Complex data types are API gateway, Json, JXPFlowAppActivity, JXPHttpRestResponse, JXPResponse, Record, WebRequest, and WebResponse.&#x20;

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* Entity-based data types are user-defined entities.

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* A variable can contain only one (1) Data Type.


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