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Latitude: a geographic coordinate that specifies the north-south position of a point on the Earth's surface.

-Latitude is an angle (defined below) which ranges from 0° at the Equator to 90° (North or South) at the poles.

-Lines of constant latitude, or parallels, run east–west as circles parallel to the equator.

-Latitude is used together with longitude to specify the precise location of features on the surface of the Earth.

Longitude: is a geographic coordinate that specifies the east-west position of a point on the Earth's surface.

-It is an angular measurement, usually expressed in degrees Points with the same longitude lie in lines running from the North Pole to the South Pole.

-By convention, one of these, the Prime Meridian, which passes through the Royal Observatory, Greenwich, England, was intended to establish the position of zero degrees longitude.

-The longitude of other places was to be measured as the angle east or west from the Prime Meridian, ranging from 0° at the Prime Meridian to +180° eastward and −180° westward.

- Specifically, it is the angle between a plane containing the Prime Meridian and a plane containing the North Pole, South Pole and the location in question.

Going back to old navigation, they divided up a degree into 60 minutes where each minute is divided up into 60 seconds.

-This is the most common format used to mark maps. It's also the most cumbersome to work with. It's a lot like telling time…

-There are sixty seconds in a minute (60" = 1') and

-There are sixty minutes in a degree (60' = 1°).

Keeping in mind a few easy conversions between seconds and decimal minutes will help when working with maps that use degrees, minutes and seconds.

15 seconds is one quarter of a minute or 0.25 minutes

30 seconds is one half of a minute or 0.5 minutes

45 seconds is three quarters of a minute or 0.75 minutes

Positive values of latitude are north of the equator, negative values to the south.

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