Описание тега outputstream

An OutputStream is an abstract mechanism for writing data to a stream in Java and C#. A stream is usually comprised of data to write to a local file, or data being transmitted to a remote server over a network protocol such as HTTP or FTP.

An OutputStream is abstract, and doesn't describe the type of data that is being written. Typically you would implement one of the subclasses instead, such as FileOutputStream, which more appropriately describes the type of data being handled, and provides additional methods appropriate for that data type.