Physics (from Ancient Greek: φυσική (ἐπιστήμη)phusikḗ (epistḗmē) "knowledge of nature", from φύσις phúsis "nature") is the natural science that involves the study of matter and its motion through space and time, along with related concepts such as energy and force. More broadly, it is one of the main analysis of nature, conducted in order to understand how the universe behaves.