Latitude and longitude are a pair of numbers (coordinates) used to describe a position on the plane of a geographic coordinate system. The numbers are in decimal degrees format and range from -90 to 90 for latitude and -180 to 180 for longitude.
For example, Washington DC has a latitude 38.8951 and longitude -77.0364. In API calls you’ll often see the numbers placed together and separated by a comma: 38.8951,-77.0364.
One common problem is mixing up the latitude and longitude. Some tools and APIs format longitude,latitude while others use latitude,longitude.