In social science people create and use mental images, termed 'mental maps', to understand their environments and to organise their knowledge of places. Children can use maps for more than way-finding. They are able to understand and use symbols and patterns represented by colour or shading. A few studies suggest that simple maps can be understood by children even without formal instruction. Different symbols are used in maps to locate and identify places and utilities e.g. use of a single cow to indicate a region of cattle raising, a blue dot represents a perennial well, and so on. Thus, to introduce the theme 'Markets' a teacher can use maps to locate major markets around the school.