Hi!
Some newer (or fancier) TV sets and VCRs support displaying this information. The information is broadcast along with the program when it is on. The information supplied can be program name, program type, station name (call letters), program rating, time elapsed, time remaining and possibly anything else so long as the receiver can decode and display it.
I believe that this information is broadcast in a way similar to the way closed captions are presently broadcast outside of the picture's normally viewable area. TV sets that support the display of this information don't seem too common...I have a lot more VCRs here that display this information.
William