Channel vs. Station
A *station* defines the lineup of content, the same program, what runs when.
Two channels are the same station, if they always runs the same program at the same time.
(Unless it's a channel shared between two stations, e.g. a cartoon station during day and a home shopping station during the night.)
A *channel* is the technical distribution. It can be terrestrical (airwaves), satellite or cable, analog or digital, SD or HD. It's quite common that the same station is distributed on T, S and C, and sometimes even both in SD and HD. The quality may differ, but it's the same program everywhere.
Recordings are made based on program listings, the station has the program listing assigned, and channels carry stations and have the physical tuning parameters.
Why differentiate? Because there are quite some users which have both T and S reception, and TV cards for both, and some (but not all) stations are receivable via both directions. When there's a conflict (two recordings scheduled at the same time) on the sat card, you may want to use the T card to record the lesser important show. Or the station is distributed via both HD and SD.
Channels can have a quality rating assigned. Quality and repetitions are considered by the scheduler, so if the T card channel has lesser quality, and the show is repeated later on the sat card, without conflict, then the scheduler will chose the latter. In other words, the lower quality card is used only when the recording could otherwise not be made at all - but it's useful in these cases.
So, the clear distrinction between stations and channels allows Zeipis to consider all this.
