A cybernetics conference was a symposium at which cybernetics was discussed.
In 2366, Data attended a cybernetics conference, after which he began to spend an inordinate amount of time in a locked lab on USS Enterprise-D. This piqued Geordi La Forge's curiosity at the android's uncharacteristic behavior.
Data later revealed to La Forge and Deanna Troi that he had begun work on Lal, his offspring, at the conference after learning of "a new submicron matrix transfer technology introduced at the conference which I discovered could be used to lay down complex neural net pathways." (TNG: "The Offspring")