Formerly Document Objects (DocObjects), ActiveX Documents are extensions to Microsoft's compound document architecture (see
OLE) that allow an application to employ the functionality of another application.
For example, Office applications are "ActiveX Documents servers." The Internet Explorer browser, starting with Version 3.0, was made an "ActiveX Documents container," which can run the server application within it. As a result, Internet Explorer can view an Excel spreadsheet or a Word document by launching the appropriate server.