Simplify the following text for a Grade 3 native English-speaking person.
Original: The term `` matter '' is used throughout physics in a bewildering variety of contexts : for example , one refers to `` condensed matter physics '' , `` elementary matter '' , `` partonic '' matter , `` dark '' matter , `` anti '' - matter , `` strange '' matter , and `` nuclear '' matter . In discussions of matter and antimatter , normal matter has been referred to by AlfvÃ n as koinomatter .
Simplified: Matter has volume .