# Chapter 8. The IO Library

* C++ use various types in std IO libraries to handle IO.

List of C++ classes to handle IO:

* `istream` (input stream) type, for input operations
* `ostream` (output stream) type, for output operations
* `cin` (an `istream` obj) reads std input
* `cout`
* `cerr` (an `ostream` obj) for program error messages, writes to std error