Edgware, where I lived in the 1940s and early 1950s, was part of the London Transport area. So all the buses were red. Most were double-deckers, but the 240A bus, which went between Edgware and Mill Hill East. was a single-decker because it had to pass under a low bridge. This was the bus that I took to my second school.
The buses had no doors, just an open platform with a vertical pole to hold onto while climbing aboard. This meant that passengers could get on and off buses while they were moving, which of course was recognised as unsafe. The trick for getting off a bus before it had quite stopped was to make sure that you were facing the direction of travel. Otherwise you would be knocked over backwards.
The platform of the double decker buses led directly to the stairs to the upper-deck and to the seats on the lower-deck.
Having no closing doors and being unheated, the buses were effectively open to the outside, letting in the cold and the fog - although they were an improvement from the buses with no roofs in my mother's childhood of the early 1900s.
In the very cold winters of 1947 and 1963, the condensation iced up the windows, and icicles grew from the ceilings. Some were 6-8 inches long.
I don't know whether any of the icicles ever broke off, but if so it would have been perilous for anyone sitting underneath. As it was, tall passengers had to duck as they moved to a seat.
I saw a lot of buses when I was growing up because the Edgware bus terminus was so close to where I lived. My first recollection was of the buses like the one in the photo with the 'eyes'. Every bus seemed to have these eyes. They were actually advertising a magazine, but, as a young child, I didn't realise this and thought that the buses were given eyes, just as my dolls and teddy bears were given eyes. After all, buses needed to see where they were going. I was quite concerned when new adverts eventually replaced the eyes.
Another advert that deserves a place here, although I hardly noticed it at the time, was the 'Make do and Mend' one which aimed to encourage everyone to cope in the rationing and shortages of the Second World War and the years of austerity afterwards.