Natural science is one of the branches of science concerned with the description, understanding and prediction of natural phenomena. Natural science can be divided into two main branches: life science
and physical science. Life science is alternatively known as biology, and physical science is subdivided into branches: physics, chemistry, earth science, and astronomy. These branches of natural science may be further divided into more specialised branches. Environmental technology or green technology, also known as clean technology, is the application of one or more of environmental science, green chemistry, environmental monitoring and electronic devices to monitor, model and
conserve the natural environment and resources, and to curb the negative impacts of human involvement.