Mercator projection
The mercator projection is the projection of part of the curved surface of the Earth onto a flat piece of paper, a map. The projection is name after the Flemish cartographer Gerardus Mercator, who introduced it in 1569. It is the most commonly applied projection in map making.
The meridians (lines of equal longitude) are equally spaced, parallel vertical lines. The parallels of latitude are mapped as parallel, horizontal straight lines, increasingly spaced as their distance from the equator increases.
The mercator projection is widely used for navigation charts, because any straight line on the map is a line of constant direction. This enables a navigator to plot a straight-line course. It is less practical for world maps because the scale is distorted; surface areas further away from the equator appear disproportionately large. On a mercator projection, for example, the area of Greenland appears to be larger than that of South America; actually, Greenland's area is smaller than that of the Arabian Peninsula.