system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Difference between Euclidean and non-Euclidean geometry?
gpt
There are 7 postulates in Euclidean geometry - baseline rules that underpin the entire logical system.

Non-Euclidean geometries involve changing the 5th postulate - also called the parallel postulate - to something else. You can look up a more formal statement, but the parallel postulate is the one that ensures that two parallel lines can never meet.

Normally, non-Euclidean geometries deal with situations where the surface you're working with is curved.