Concepts for Extending the User Interface Layer in the vSphere Client

There are three main concepts in vSphere Client UI extensibility.

Extension point	An integration point on the vSphere Client user interface where a plug-in can hook and add its own capability.
Extension	The UI content that you want to visualize. This can be views, menus or any other UI controls.
Extension ID	A unique identifier that you define to refer to your extension.