Caffeine is arguably the world's most well-known psychoactive substance. Millions of people start their day with a cup of coffee or tea to stay alert and focused. But what exactly is caffeine? How is it produced in plants, and what chemical processes occur in the body when we consume it?

Coffee has become a faithful companion in our fast-paced everyday lives. The first cup of coffee follows in the morning after we wake up. But what is a pleasure for us tells a historical and contemporary story of forced labor, poverty, violence, and environmental destruction in other places.

The legend of coffee is rich in stories and myths. One of the most famous is the story of the Ethiopian shepherd Kaldi. According to legend, Kaldi lived in the Kaffa region of present-day Ethiopia, where he grazed his goats.