Hi swamy.
in
java there are three Streams which are always open .
System.in
System.out
System.err
in ---> This is the instance variable declare inside class InputStream
out---> This is the instance variable declare inside class Printream
err---> This is the instance variable declare inside class PrintStream
all Three are public ,static and final
and all three are related to standard stream (input ,output ,error) that's they called as stream variables.
i hope it's clear now if any mistake please do back.
vishwas