An InputStream handles byte data.
InputStream is an abstract class from which all
byte-oriented input streams are derived.
Its descendant classes are used for general-purpose input
(non-character input).
These streams
deliver data to a program in groups of 8-bit bytes.
The bytes can be grouped into the size necessary for
the type of data.
Unlike Readers and Writerss,
no transformation of bytes is performed.
If you input data from a disk file using a decendant of InputStream
what is on the disk is exactly what you get.
This is what you want for many types of data: audio, image, database, machine code....
For example,
if a disk file contains 32-bit int data,
the program can read exactly those bits in 4-byte groups.
We will be mostly concerned with DataInputStream
and FileInputStream.
(Review: ) What type of data does an OutputStream handle?