Oh i keep forgetting that ( plugins)
Then let me add that it's name depends on the program.
Cubase: group channel or effects channel
Protools: aux channels or group channels
Mixbus: mixbus channels or group channels
All these are used to add delay/reverb and effects to multiple tracks by using the send option.
The source channels will be send to an ( aux,group,mixbus) channel.
The aux,group or mixbus channel gets the effect plugin.
Both the source channel as the effect channel are send to the "main" channel or bus for further processing or recording.
Aren't the wonders of the digital age delightful?