Dynamics 365 Root objects in the Client API object model

At the root of the Client API object model are the following contexts and the Xrm object:

Object	Description
executionContext	Represents the execution context for an event in model-driven apps forms and grids. More information: Client API execution context
formContext	Provides a reference to a form or an item on the form against which the current code executes. To get the formContext object, use the executionContext.getFormContext method. More information: Client API form context
gridContext	Provides a reference to a grid or a subgrid on a form against which the current code executes. More information: Client API grid context
Xrm	Provides a global object for performing operations that do not directly impact the data and UI in forms, grids, subgrids, controls, or attributes. For example, navigate forms, create and manage records using Web API. More information: Client API Xrm object