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”).