While studying geography as a kid, we all dealt with maps and charts that seemed to be nothing more than a conundrum at that point of time. They are graphical representation of relief features of earth and make for an easy understanding of the topography of a particular place. Both maps and charts are used in oceanography, which are used to help a mariner while navigating through waters.
Maps
Maps are pieces of paper with representation of physical features of earth’s surface at a particular place down to a much smaller scale to fit on the paper. Anyone having the knowledge of reading a map can retrieve all information about a place seeing its map. Reading a map is all a person needs to know the physical features of a place and decide on action. While earth is three dimensional, a map is a 2D model of the earth. These days there is a trend to make use of topographical maps that are 3D just as earth is. A map consists of lines and symbols of various colors that represent mountains, rivers, and other relief features.
Charts
A chart is a map too, but it is used for a special purpose; that is to help in navigation through water bodies. Water bodies are depicted in detail in charts with the inclusion of navigational aids, as well as, information about depth of water at different places in the water body. Most beginners make the mistake of referring to charts as maps. Charts include level of tides along a coastline in a very detailed and accurate manner, making them helpful to a mariner. A shoreline may be there in a map though not much emphasis is paid to it.
What is the difference between Maps and Charts? • A chart is a working document, whereas a map is a static one. This means that maps can only help in following roads, trails, highways etc that have been mapped but do not inform about the quality of road, rough conditions or any obstructions that a person may encounter. Map only provides directional guidelines as to how and when to take a turn. • Charts are updated all the time and can be used by mariners, as they know the area beneath the water body that proves to be critical for their safety. • Charts provide accurate information about a coastline, whereas maps do not tell anything about the condition of the roads.
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