[C++ Basic] Lesson 6. Input/Output in C/C++
Basic Input/Output
Until now, the example programs of previous sections provided very little interaction with the user, if any at all. Using the standard input and output library, we will be able to interact with the user by printing messages on the screen and getting the user's input from the keyboard.
C++ uses a convenient abstraction called streams to perform input and output operations in sequential media such as the screen or the keyboard. A stream is an object where a program can either insert or extract characters to/from it. We do not really need to care about many specifications about the physical media associated with the stream - we only need to know it will accept or provide characters sequentially.
The standard C++ library includes the header file iostream, where the standard input and output stream objects are declared.
Standard Output (cout)
By default, the standard output of a program is the screen, and the C++ stream object defined to access it is cout.
cout is used in conjunction with the insertion operator, which is written as (two "less than" signs).