"Object Linking and Embedding" [1] is:

• a previous label for COM
• the Microsoft technology of the mid-'90s which best implemented "lock-in"
• a brand along the path from DDE to ActiveX and COM (and eventually .NET)
• the technical basis of what has arguably been the world's only successful "component" marketplace, that of "OCX controls"
• an interesting scripting interface

Nowadays, it's largely a relic, visible mostly in the antique portions of COM. The ROT is a remnant of this time that remains significant for contemporary development and administration.

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