In computer science, source code (commonly just source) is any collection of statements or declarations written in some human-readable computer programming language. Source code allows the programmer to communicate with the computer using a reserved number of instructions.

Latitude lines go East/West around the Earth, like a belt goes around your body (this may be kind of rude, but it's easy to remember because "latitude" sounds like "fatitude" and how big your belt is depends on how skinny/fat you are). If you are in the Northern hemisphere (US/Canada/Mexico/Europe/Asia), then if you go North, the latitude increases, and if you go South it decreases. It's the opposite in the Southern hemisphere. The equator is 0 latitude.

Longitude lines are the opposite. They go North/South (like a the tie on a man in a suit). 0 Longitude goes through London. If you go East or West of there, the numbers get bigger.

Maps usually show these lines as a grid – they can be straight or gently curved depending on how the map is drawn. If you follow one of the grid lines to the edge of the map, it will say what latitude or longitude that line represents. So, numbers on the left or right side of the map indicate latitude, and numbers along the top or bottom of the map represent longitude.