What is ActiveX (used in some websites)?

An ActiveX control is essentially a simple OLE object. Originally, ActiveX controls were called "OLE controls" and used a .ocx file extension. This was actually the second-generation component architecture. The first generation was the Visual Basic Controls (.vbx). OLE controls were renamed ActiveX and continue to use the .ocx extension. ActiveX controls enable a program to add functionality by calling ready-made components that blend in and appear as normal parts of the program. They are typically used to add user interface functions, such as 3D toolbars, a notepad, calculator or even a spreadsheet.

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