Maps

Navigation is simple today.  Give your cell phone a destination and then follow step by step directions.  

However, in the not so distant past, directional travel wasn't that easy.

Long before the Global Positioning System, travelers were dependent on the sun, moon and the stars for direction.  Sailors came to depend on wind directions as well.  They used compasses, sextants, hourglasses, astrolabes and a lot of dead reckoning. Cartographers added rhumb lines, windroses, and Latitude & Longitude grid lines to their maps. One of the most difficult problems was determining longitude at sea and it took until the late 1700's to solve.

The rise of air travel in the 1930's boosted the desire for a coordinate system.  With the arrival of satellites in the 1950's & then the Moon landings, a Global Positioning System became necessary.   Developed by the military, GPS was released to the civilian world in 1983 in a somewhat scrambled inaccurate form.  Then in May 2000, GPS was unscrambled with an accuracy of 10 yards.

In the years since, GPS has become more accurate and is now used in a vast number of applications.

But every now and then...someone ends up in a lake...

Latitude and Longitude have confused English speaking people for years. 

So how to get them correct?  Here is a simple way to remember:

Latitude is the Equator, the Tropic of Cancer and the Tropic of Capricorn on a globe.  It goes around the globe--left and right.  There are 180 latitude lines.

Longitude is the Prime Meridian or Time Zones.  It goes up and down on the globe. There are 360 longitude lines.

Why were Time Zones Created?

The short answer is long distance travel and communications.

Prior to the 19th century, local solar time worked pretty well.  But with the rise of railroads, a system needed to be created for passengers to know when to meet their train.

The International Meridian Conference in 1884 chose Greenwich for the Prime Meridian and based Greenwich Mean Time from there with the 24 hour division.

In some places the Time Zone lines don't follow the meridians.  This can be easily seen at the International Date Line located in the Pacific Ocean.  For political or cultural reasons, some countries want to be on the same time. This can have interesting results...