In the main the actors playing the parts were changed from Season to Season. Therefore all characters carry an S number which refers to the Season(s) in which that actor appeared in that part. This is also necessary as children do grow up. This also means that the character/actors are in chronological order not by number of appearances as is usual. Characters which begin with a Capital G are Ghosts or phantoms etc. and their images were intentionally blurred, out of focus and, sometimes, were of a different colouring when aired.