Technically you are not allowed to ride on the pavement unless you are delivering mail such as leaflets (or the council has put a ‘magic’ signpost saying that that particular pavement is in fact a bike lane as well as a pavement) – in reality,  if you are an inexperienced or nervous rider and the road is very busy, the pavement is often the best place to ride. Please ensure that you go slowly, are courteous and give way to pedestrians (in the same manner that you would if the pavement had a ‘magic’ council sign).
86 million everyday utility cyclists from all walks of life ride their bicycles on the pavements in Japan.
Being able to ride on pavements opens up cycling to the vast majority of us who will never entertain the idea of sharing the road with motor vehicles.
For a bit of history on the prohibition against cycling on pavements, see: http://sites.google.com/site/urbanbicycles/pavements
I agree with Unity that, in reality, there are places where riding on the footpath for a short period is the safest and most pleasant course of action. Many cyclists have a severe mental block about doing this as a practical alternative!!!!
It is absurd, that a cyclist cannot legally ride on a deserted pavement, when it is vastly safer to do so.