C++ Primer Plus

Using cin

As the output from Listing 2.3 demonstrates, the value typed from the keyboard (12) is eventually assigned to the variable carrots. The following statement performs that wonder:

cin >> carrots;

Looking at this statement, you can practically see information flowing from cin into carrots. Naturally, there is a slightly more formal description of this process. Just as C++ considers output to be a stream of characters flowing out of the program, it considers input to be a stream of characters flowing into the program. The iostream file defines cin as an object that represents this stream. For output, the << operator inserts characters into the output stream. For input, cin uses the >> operator to extract characters from the input stream. ...