System is a class in java.lang. It includes a field called "out" that references a PrintStream that is "already open and ready to accept output data. Typically this stream corresponds to display output or another output destination specified by the host environment or user."
PrintStream is a class in java.io. It includes a method called "println" overloaded to take many different argument types, which are basically streamed out then terminated "by writing the line separator."
"We're kind of on the level of crossword puzzle writers... And no one ever goes to them and gives them an award." ~Joe Strummer sscce.org