Answer:
A stream of characters is input (from a file) and later a stream of characters is output (often to the same file).
A stream of characters is input (from a file) and later a stream of characters is output (often to the same file).
Some programs read in the entire input stream before they write the output stream. Other programs read the input stream item by item and write one output item for each input item. There are many other patterns of input and output. In general, a program may have several input streams flowing into it and several output streams flowing out of it.
There are three standard I/O streams:
Normally System.in is connected to the keyboard
and the data are characters.
System.out and System.err both are connected
to the monitor, and also contain character data.
These notes use System.err only occasionally.
What does the keyboard send to your program when you type the following:
1234