When you write a souce code with C language, you need to build the souce code to machine languag to run it. With C, you can use GCC. For example: $ gcc hello.c -o hello With C++, you can use G++. Fore example $g++ hello.cpp -o hello Ref: http://stackoverflow.com/questions/172587/what-is-the-difference-between-g-and-gcc
When