Qjackctl entries

Hi
In the Qjackctl=>connect window (also within Ardour) are entries I do not understand:
MMC
MTC
LTC
What is the meaning of these abbreviations, and what effect do they have on Ardour ?

Thanks for your help

Midi Machine Control
Midi Time Code
Linear Time Code

The short version is if you don’t know what they are you probably don’t need to worry about it.

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