SAP is a behemoth comprised of dozens of functional modules, several of which involve manufacturing. At its heart, though, SAP is an accounting system. Most companies that use SAP also prefer to use one or more dedicated/proprietary/best-of-breed manufacturing systems for certain specialized functions. In such an environment, both SAP and the other systems work best if they can share real-time data, maintaining one version of the truth. Manufacturing Integration refers to this process of sharing such data between disparate systems and applications typically found in manufacturing plants and industrial facilities.