There are two possible round signs with human stick figures.
Round, white, with a red border means pedestrians prohibited, which can apply anywhere that an appropriate traffic order has been made.
Round and blue indicates that the path is for pedestrians only. It is one of a small group of path signs, the others being a flying bicycle over the figures, which means the path is to be shared by pedestrians and cyclists, a bike and figure side by side, with a vertical line between them, which shows that there are separated paths for cyclists and for pedestrians, and a bike by itself, which shows the path is for cyclists only.
The Highway Code is not comprehensive. For that you need a copy of the Traffic Signs Regulations and General Directions 2002, although the DoT booklet Know Your Traffic Signs is nearly as good.
Colin Bignell