Binary File

Of course, fundamentally all files consist of
8-bit bytes.
As far as the computer’s electronics are concerned,
all files look alike.
The electronics of the hard drive, the hard drive controller, and the
bus that connects them to the rest
of the computer system are concerned only with
storing and retrieving bytes.
They move bytes back and forth between components without
concern about what the bytes mean.

But humans like to make a distinction between types of files.
Those files that contain bytes which are interpreted as
characters (only) are called “text files.”
All other files
are called “binary files.”
You may wish to look again at Chapter Two
to review the ideas of bit patterns and representation.

The terms “text file” and “binary file” are somewhat misleading.
For example, a word processor file is a “binary file.”
This is because many of the bytes
in a word processor file
are interpreted as font,
formatting, graphics, and other non-character information.
These bytes use all 256 patterns.

The picture shows the top of the IO stream hierarchy.
This chapter will look at the OutputStream class.