Reduce, reuse - and recycle.
The last of the "three Rs," recycling gives fresh value to the natural resources that are tapped to produce products for consumption. Recycling can benefit the environment by reducing waste - and it's also big business.
The average person in Senegal produces about 116 kilograms of waste per year. But a group of students in the West African country is trying to change that. At a summer workshop in Dakar, they came up with an app prototype to try and get people recycling.