It only happens in plant. It transfers light energy into chemical energy.
Simple inorganic compound –light energy–> complex organic compound
Photosynthesis occurs in Chloroplast. In the Chloroplast, there is organelle called chlorophyll that makes photosynthesis to happen. Plants take Carbon Dioxide (CO2) in and water (H2O) and turns them into oxygen and protein. This is how they make food for themselves.