<P> Climatic maps are often incorporated into climatic atlases of varying geographic range (globe, hemispheres, continents, countries, oceans) or included in comprehensive atlases . Besides general climatic maps, applied climatic maps and atlases have great practical value . Aeroclimatic maps, aeroclimatic atlases, and agroclimatic maps are the most numerous . </P> <P> The various features shown on a map are represented by conventional signs or symbols . For example, colors can be used to indicate a classification of roads . Those signs are usually explained in the margin of the map, or on a separately published characteristic sheet . </P> <P> Some cartographers prefer to make the map cover practically the entire screen or sheet of paper, leaving no room "outside" the map for information about the map as a whole . These cartographers typically place such information in an otherwise "blank" region "inside" the map--cartouche, map legend, title, compass rose, bar scale, etc . In particular, some maps contain smaller "sub-maps" in otherwise blank regions--often one at a much smaller scale showing the whole globe and where the whole map fits on that globe, and a few showing "regions of interest" at a larger scale in order to show details that wouldn't otherwise fit . Occasionally sub-maps use the same scale as the large map--a few maps of the contiguous United States include a sub-map to the same scale for each of the two non-contiguous states . </P> <P> To communicate spatial information effectively, features such as rivers, lakes, and cities need to be labeled . Over centuries cartographers have developed the art of placing names on even the densest of maps . Text placement or name placement can get mathematically very complex as the number of labels and map density increases . Therefore, text placement is time - consuming and labor - intensive, so cartographers and GIS users have developed automatic label placement to ease this process . </P>

What are some physical features that can be shown on a map