System – is a final class and cannot be instantiated. Therefore all its members (fields and methods) will be static and we understand that it is an utility class.
Systemclass are standard input, standard output, and error output streams.
out – is a static member field of System class and is of type PrintStream. Its access specifiers are public final. This gets instantiated during startup and gets mapped with standard output console of the host.
println – Method of PrintStream class. println prints the argument passed to the standard console and a newline.