Active Documents (previously referred to as OLE documents) are a set of COM services that support linking and embedding, drag-and-drop, and visual editing. Active Documents can seamlessly incorporate data or objects of different formats, such as sound clips, spreadsheets, text, and bitmaps. 

Unlike ActiveX controls, Active Documents are not limited to in-process servers; they can be used in cross-process applications. 

Unlike Automation objects, which are almost never visual, Active Document objects can be visually active in another application. Thus, Active Document objects are associated with two types of data: presentation data, used for visually displaying the object on a display or output device, and native data, used to edit an object. 

Active Document objects can be document containers or document servers. While Delphi does not provide an automatic wizard for creating Active Documents, you can use the VCL class, TOleContainer, to support linking and embedding of existing Active Documents. 

You can also use TOleContainer as a basis for an Active Document container. To create objects for Active Document servers, use the COM object wizard and add the appropriate interfaces, depending on the services the object needs to support. For more information about creating and using Active Document servers, see the Microsoft ActiveX Web site.