The Common Data Model is a declarative specification, and definition of standard entities that represent commonly used concepts and activities across business and productivity applications, and is being extended to observational and analytical data as well.
CDM provides well-defined, modular, and extensible business entities. Anyone can build on and extend CDM definitions to capture additional business-specific ideas.
The Common Data Model standard defines a common language for business entities covering, over time, the full range of business processes at the core of a company's business processes.
The goal of CDM is to enable data and application interoperability spanning multiple channels, service implementations, and vendors.
CDM provides self-describing data (structurally and semantically), enabling applications to easily read and understand the data.