Could you imagine if there were a bunch of lines all over the Earth,
that people could use to make maps and figure out where things were at on the planet?
Well there aren't really lines, but people have made up imaginary lines called latitude and longitude.
(from: wikipedia - latitude)
latitude is the word we use for the lines that go side to side,
and longitude is for the lines that go up and down.
Using those lines you can tell exactly where a place is on the map!
For latitude, the equator is in the middle so it is at 0° latitude.
The North pole is at 90° (or 90°N), and the South pole is at -90° (or 90°S).
For longitude, the 0° mark is at the prime meridian.
You can go East all the way to 180° (or 180°E) and West all the way to -180° (or 180°W).
For example, Detroit, MI is located at: 42.35, -83.05