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===Mercator===
 
===Mercator===
 
[[File:MercatorProjection.jpg|frame|The Mercator projection]]
 
[[File:MercatorProjection.jpg|frame|The Mercator projection]]
The {{w|Mercator projection}} was introduced by Flemish cartographer Gerardus Mercator in 1569. The main purpose of this map is to preserve compass bearings; for example 13 degrees east of north will be 13 degrees clockwise from the ray pointing toward the top of the map, at every point.  A mathematical consequence is the mapping is conformal, i.e. if two roads meet at a certain angle on the surface of the Earth, they will meet at that same angle on the map.  It also follows that at every point the vertical and horizontal scales are the same, so locally i.e. considering only a small part of the map, geographical features (shapes, angles) are well represented, which helps a lot in recognizing them on-the-field, or for local navigation in that small part only. For this reason, that projection (or a close variant) is used in several online mapping services (such as Google Maps when this comic was published, but they switched to a globe, see below), which means that it is frequently encountered by the general public. A straight line on the map corresponds to a course of constant bearing (direction), which was very useful for nautical navigation in the past (and thus made that projection very well-known).
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The {{w|Mercator projection}} was introduced by Flemish cartographer Gerardus Mercator in 1569. The main purpose of this map is to preserve compass bearings; for example 13 degrees east of north will be 13 degrees clockwise from the ray pointing toward the top of the map, at every point.  A mathematical consequence is the mapping is conformal, i.e. if two roads meet at a certain angle on the surface of the Earth, they will meet at that same angle on the map.  It also follows that at every point the vertical and horizontal scales are the same, so locally i.e. considering only a small part of the map, geographical features (shapes, angles) are well represented, which helps a lot in recognizing them on-the-field, or for local navigation in that small part only. For this reason, that projection (or a close variant) is used in several online mapping services, such as Google Maps, which means that it is frequently encountered by the general public. A straight line on the map corresponds to a course of constant bearing (direction), which was very useful for nautical navigation in the past (and thus made that projection very well-known).
  
 
However, from a global point of view, this projection is radically incorrect in how it shows the size of landmasses (for instance, Antarctica and Greenland seem gigantic), and furthermore, it always excludes a small region around each pole (otherwise the map would be of infinite height), so it doesn't provide a complete solution for the problem of map projection. The comic implies that people who like that projection aren't very interested with map issues, and typically use what they are offered without thinking much about it.
 
However, from a global point of view, this projection is radically incorrect in how it shows the size of landmasses (for instance, Antarctica and Greenland seem gigantic), and furthermore, it always excludes a small region around each pole (otherwise the map would be of infinite height), so it doesn't provide a complete solution for the problem of map projection. The comic implies that people who like that projection aren't very interested with map issues, and typically use what they are offered without thinking much about it.
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To quote ''{{w|The Princess Bride}}'': "Yes, you're very smart. Shut up."
 
To quote ''{{w|The Princess Bride}}'': "Yes, you're very smart. Shut up."
  
A globe is, of course, the "map projection" used by {{w|Google Earth}}, and recently by other mapping software (including Google Maps) as computers and phones get increasingly powerful 3D graphics.
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A globe is, of course, the "map projection" used by {{w|Google Earth}}, and recently by other mapping software as computers and phones get increasingly powerful 3D graphics.
  
 
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