Which human activities are changing our climate, and does climate change constitute a major problem? We will investigate these questions through an introduction to climate processes and an exploration of climate from the distant past to today. We will also consider the impact of past and ongoing climate changes on the global environment and on humanity. Finally, we will draw on climate science to identify and evaluate possible courses of action. Intended to be accessible to students not concentrating in science or engineering, while providing a comprehensive overview appropriate for all students.