## TL;DR
The Köppen climate classification (Wladimir Köppen, 1884) categorizes world climates into 5 main groups: A (Tropical), B (Arid/Desert), C (Temperate), D (Continental), E (Polar). Further subdivided by precipitation and temperature patterns. Most widely used climate classification system.
## Core Explanation
A Tropical: year-round warm, high rainfall — rainforest (Af), monsoon (Am), savanna (Aw). B Arid: evaporation exceeds precipitation — desert (BW), steppe (BS). C Temperate: mild winters — Mediterranean (Cs), humid subtropical (Cfa), marine west coast (Cfb). D Continental: cold winters, warm summers — only in Northern Hemisphere. E Polar: tundra (ET), ice cap (EF). Highland (H): mountain climates.
## Further Reading
- [Köppen Climate Classification](https://www.britannica.com/science/Koppen-climate-classification)