Definition of stream class: An I/O Stream represents an input source or an output destination. A stream can represent many different kinds of sources and destinations, including disk files, devices, other programs, and memory arrays. Streams support many different kinds of data, including simple bytes, primitive data types, localized characters, and objects. Java’s stream based I/O is built upon four abstract classes: InputStream, OutputStream, Reader, Writer.
Types of stream classes:
i. Byte stream classes
ii. Character stream classes.