x, y, z coordinates
Z coordinatesx and y coordinates are in 2-D (flat) while coordinates with a z-coordinate are in 3D. The world is in 3D and not 2D. You can zoom in, move sideways, or move up and down. This is why the Z-coordinate is necessary. A graph with the Z-coordinates is shown below. [IMAGE] All the Z-coordinates do is extend the normal 2-D x-y coordinates by giving it a third direction so that all positions then have 3 coordinates (x, y, z).Having 3 coordinates means you can give the coordinates of the ends of a book or any other 3-D shape. An example is shown below. [IMAGE] For the graph above the coordinates of B are (7, 4, 0) and the coordinates of F are (7, 4, 2)
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