Latitude & Longitude Grids

• Lecture: The Geographic Grid, Dr. Rodrigue
  The geographic grid is built of intersecting great and small circles with with half-great circles. Hunh?
  (tags: grid longitude latitude circles)
• Cartographic Projections
  Cartography is an ancient art and science of methods to project -- mathematically transform all or part of the surface of a sphere
  (tags: maps)
• The Planet Earth
  Earth is almost a perfect ball. The Earth is slightly pear shaped - peaked at the North Pole and bulbous at the South Pole. The technical term for the shape of the Earth is an oblate spheroid.
  (tags: parallels latitude meridians longitude)