Java IO :
The Java Input/Output (I/O) is a part of java.io package. The java.io package contains a relatively large number of classes that support input and output operations. The classes in the package are primarily abstract classes and stream-oriented that define methods and subclasses which allow bytes to be read from and written to files or other input and output sources. The InputStream and OutputStream are central classes in the package which are used for reading from and writing to byte streams, respectively.
System:-It is the final class and its constructor is
private.so we can not create new object of System.
out. it is the static member of the System class of type
println:-it is the overload function of PrintStream.
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