What does 'stream' mean in C?

Question

I\'m reading a section in \'C Primer Plus\' which deals with files, streams and keyboard input. The author connects the concept of stream with files and defines stream as follow

Answer 1

The people designing C wanted a uniform way of interfacing with different sources of sequential data, like files, sockets, keyboards, USB ports, printers or whatever.

So they designed one interface that could be applied to all of them. This interface uses properties that are common to all of them.

To make it easier to talk about the things that could be used through the interface they gave the things a generic name, streams.

The beauty of using the same interface is that the same code can be used to read from a file as from the keyboard or a socket.