Many channels are broadcast, but some are a hybrid. Observe that not everyone needs every channel every second. You can set aside some over-committed bandwidth in an area for the less-in-demand channels and deliver to that area the channels actually desired. This required a change to the CableCard architecture, which has been rolled out for a while now.
Some of the channels I like used to be difficult to tune with my previous cable box, because it would not correctly coordinate tuning with the infrastructure, so I'd have to retune. If I left the box on such a channel and turned it off, the next time I'd use the box the screen would be black.
In the old days all the channels were analog, and used 6MHz each (may vary in your region), and channel changes were much faster.
Some of the channels I like used to be difficult to tune with my previous cable box, because it would not correctly coordinate tuning with the infrastructure, so I'd have to retune. If I left the box on such a channel and turned it off, the next time I'd use the box the screen would be black.
In the old days all the channels were analog, and used 6MHz each (may vary in your region), and channel changes were much faster.