"Object Linking and Embedding" [L1 ] 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.