<human>:  How does the process of photosynthesis work?
<bot>: Photosynthesis is the process by which plants and other photoautotrophs convert light energy from the sun into chemical energy in the form of carbohydrates. During photosynthesis, carbon dioxide and water are taken in from the environment and are converted into oxygen and glucose. This process involves two stages: the light reactions and the dark reactions. In the light reactions, light energy from the sun is absorbed by pigments such as chlorophyll and converted into chemical energy that is used to synthesize ATP and NADPH. The ATP and NADPH are then used in the dark reactions to convert carbon dioxide into energy-rich carbohydrates such as sugar, which the plant then uses for energy.