The Usual C++ Header Files
Part of the C++ All-In-One For Dummies Cheat Sheet
In C++, a header file holds forward declarations of identifiers. Here are some of the most common C++ header files that you’ll be using, along with their correct spellings. These aren’t by any means all of them, but they are the most common:
Include <string> if you’re going to be using the string class.
Include <iostream> when you want to use cout and cin.
Include <fstream> when you want to read or write files.
Include <iomanip> if you want advanced manipulator usage in your streams.
Include <stdlib.h> for general operations, including system(PAUSE).