Ok , this is a hopeless anoraky question but something I suddenly wondered
last night... How come most bus routes have a simple number (eg 13, 221) but
some have a letter in them , eg W6. Why do some routes have letters too? Its
not like they've used up all the numbers in the universe so do these letters
denote something special (ok , I know what the N in the night bus routes mean ,
I'm talking about daytime routes)?

B2003