HTML components display the visual components of the vSphere Client interface. You can create custom HTML components to add new features to the user interface.

Flex user interface components display the visual components of the vSphere Web Client interface. You can create custom Flex components to add new features to the user interface.

Data Service Adapters implement query service interfaces designed by VMware for data requests from user interface components. Property Provider Adapters and Data Provider Adapters are the two kinds of Data Service Adapters.

Data Provider Adapters implement the DataProviderAdapter interface. They respond to requests for data from custom vSphere objects or from objects that are not managed by vSphere.

Property Provider Adapters implement the PropertyProviderAdapter interface. They respond to requests for properties of vSphere objects. Property Provider Adapters cannot provide properties for custom objects.

Custom Java services provide operations on vSphere managed objects or external data sources. Custom services usually dispatch requests to vCenter Server or to external processes that perform extensive operations.