C/C++ Your Programming environments : IDE 
Know your environment : Integrated Development Environment (IDE).
  • Borland
  • Quincy
  • Visual Express C++
  • Eclipse and NetBeans with plugins.
  • Review this article to understand, why you should care your IDE types? Link: Basic_Understanding3.htm

Borland and Quincy compilers :  The basic core of C++ programming lies in modularity, meaning a set of functions in a folder that support the out put through the compiler. If you note a file, "iostream.h", a "header file"  of a C/C++ library. These are pre-configured and ready to use, and these files will support the compiler to run your applications.

Below shows the texts in that file.

Quincy compiler

Eclipse Applications with the plugins for C/C++

File Types :

These modules are portable
What goes as include ? all the header files those will function as preprocessor,
Lines beginning with a pound sign (#) are directives for the preprocessor. They are not regular code lines with expressions but indications for the compiler's preprocessor. In this case the directive #include <iostream> tells the preprocessor to include the iostream standard file. This specific file (iostream) includes the declarations of the basic standard input-output library in C++, and it is included because its functionality is going to be used later in the program.