# Chapter 3. Programok

Now that KDevelop installed successfully and the most commonly used options are set, you are probably wondering if it keeps what it promises. This Chapter gives you a guideline to how programs are created using the GNU tools in general and especially what part KDevelop plays in this game.

# 3.1. A Fordító

The Compiler is actually the program on your system that has to be installed as a minimum to create running programs; he is the one that compiles the source code into object files and creates the program.

Normally, you would start like this: Open an editor of your choice - don't use a word-processor. Type in something like this to create the source for your first program:

     #include <iostream.h>

     int main(){

     cout << "Hello World" << endl;

     }

Well, actually all the program will do is to print out the string "Hello World" to your standard output . But this is just the source code for the program to be build, not the program itself. Therefore, we need a Compiler , in this case a C++-Compiler like g++. Then we can save the file with the source code, as, let's say, myprogram.cpp and invoke the Compiler with the filename (on a console):

     g++ -o myprogram myprogram.cpp

Then we can start our program- just type `myprogram` on the console, and the program prints out the string; then exits.