OData uses HTTP, AtomPub, and JSON as its core functionalities. OData is an open protocol that allows the creation and consumption of queryable and interoperable RESTful APIs in a simple and standard way. OData builds on HTTP as the application protocol for transferring data between clients and servers. OData uses AtomPub as one of the formats for representing data feeds and entries in XML. OData also uses JSON as another format for representing data feeds and entries in a lightweight and human-readable way. Reference: Introducing OData - SAP Learning, OData Overview | OData - The Best Way to REST