Various authors have categorized different types of maps in alternate ways. However, there are several distinct broad types of maps. Some may fall into more than one type in this classification. There may also be some maps that do not fit into these types. Nevertheless, each type is clearly distinguishable from another because of their properties and intended functions.
• Cadastral Maps – Cadastral maps are very large- scale maps generally created by local governments, particularly in the United States, to record ownership of land parcels. These are carefully surveyed maps made byprofessional surveyors that show great localized detail so that the boundaries of parcels can be clearly delineated and identified. In the past, paper parcel maps were kept primarily in county courthouses so that they were ready to be copied, used, and re-recorded because of the sale of properties. In many cases, cadastral maps are also used to determine the amount of tax that should be levied on a property because these maps show the size of each piece of property. Today, most counties in the United States have converted these paper maps into digital format so that they can be retrieved and updated easily.
• Route Maps – Route maps are those that are specifically created to guide us from one place to another. They provide us with clues to move about and reach our intended destinations. Since humans travel on land, on water, and in the air, these route maps include navigation or sailing charts, aeronautic charts, and the traditional folded paper maps that were kept in our cars for many decades. Today, with GPS technology, people often opt for the convenience of voice-guided GPS navigation maps and systems that are built into our cars’ dashboards or delivered from our cell phones. They are very effective in guiding us through our routes. However, as accurately as GPS maps may perform, they are not 100% fool-proof. Roads, highways, and bridges continue to be constructed on our daily landscapes; the frequency with which GPS map databases are updated can dictate how well they work. In addition, a GPS referenced map can unfortunately be made based on an inaccurate map. Thus, it is always advisable to exercise some caution when using GPS maps and directions. It is important to learn to realize situations when you have been led to the wrong place by GPS instructions.
• Thematic Maps – Thematic maps are maps with specially selected topics. These may be poor in reference information, but are to illustrate a particular theme to highlight a particular event in a particular space at a specific time. A map depicting population density (or any special topic or theme) is considered a thematic map. If there is a way to collect data or information about a topic that can be represented spatially, a thematic map can be created. Some of the largest government agencies specialize in producing large volumes of thematic maps. The census bureaus and statistical agencies are often the largest departments in nations. While statistics provide large amounts of information in tabular or spreadsheet format, thematic maps have the distinctive advantage of showing spatial patterns that allow us to quickly visualize concentrations and sparseness. Thematic maps can also be non-statistical; for instance, an urban land use-themed map may depict areas of land in an urban setting, defining the zones of commercial and retail land, single-family housing, multi-family housing, transportation corridors, institutional land (schools, colleges, hospitals, prisons, etc.), recreational land, and so on. Yet, none of these land classification categories are statistical.
Because of the great usefulness of thematic maps in geography and the magnitude and variety of property details that can go into thematic maps, a continued explanation of thematic maps in greater detail continues below. amounts of detail of properties of thematic maps, another section of explanations of thematic maps shall be presented below.
• PhotoMaps –Phillip Muehrcke, in his book titled Map Use (Muehrcke, 1978, 1st edition), first labeled this group of maps as PhotoMaps. In later editions, the term “Image Maps” is used. Regardless of nomenclature, these are meant to include all non-line-drawn maps or non-line-art maps such as aerial photographs, satellite images, radar images, thermal images, and other realistic images of the land. Since then, the sophistication of these images has increased so much that most mapping scientists and the general public would treat image maps as maps. The most popular form of this class of maps is Google Earth. They show no statistics and are mostly devoid of line drawings, containing only the actual image of the land sensed from above at whatever resolution afforded by the sensing instruments. Interpretation of these images requires a totally different kind of training than the interpretation of reference maps or thematic maps.
• Animated and Interactive Maps – The availability of advanced computer graphics and Geographic Information Systems (GIS) software allows the cartographer to create dynamic maps that include animations and interactive learning activities. Some of these are even created in real- time, virtual reality, and in three-dimensions with rotational views. They may even be linked to remote video cameras. Animated maps have been appropriately applied to spatial phenomena that occur over time as well as phenomena that move from one space to another. The use of multimedia to illustrate maps can be very effective. These maps have been used in secondary education to some extent and their use continues to be encouraged. The fact that these maps can be delivered to our tablets and cell phones makes them some of the most versatile spatial education tools.
• Other Specialty Maps – In addition to the major types of maps above, there are certainly other forms of maps that are quite specialized. It would be difficult to list all specialty maps since innovations continue to appear on the scene regularly. Researchers have identified several broad groups of specialty maps that are worth mentioning here: tactual or tactile maps, mental maps, and cartograms. Tactual or tactile maps are those made especially for people with visual difficulties. Mental maps are maps or images of places in our minds based on our experience of having seen the place before or based on the ability of our minds to conceptualize the space that can be described to us. A Cartogram is a map type that distorts geographic space by sizing each geographic unit to show a special concentration of that particular set of data; for instance, on a population cartogram of the world, China would be the largest because it has the largest population and India would be second largest even though Russia is the largest in area.