Hello World program is not just about printing a message in the screen, it is about getting started with the programming language of your choice
The
Hello World program, beyond its simplicity, hides a vast amount of information needed to get started in the programming world.
The first thing it shows is the overall structure of a program for a given language. Some languages are easy and you can just start typing instructions, but others requires some structure, a scaffold that needs to be built before you can write your very first instructions in that programming language.
The second important thing this program introduces, in an indirect way, is the setup of the development environment, everything you need to install and execute in order to build and run that program which, again, is not that trivial.
Finally, specifically in the GNU/Linux Programmer's Solver book we have included, in this program two additional concepts to get introduced straight away. The first is the use of comments in each programming language. Adding comments is important for other people to understand your code so it is good to learn how to do this as soon as possible. The second is the definition of strings. In the old days, a string was a string, but different programming languages allows for different kinds of strings that can be defined in very different way. Strings are a key concept for programming languages as they are the main mean of the program to communicate results to the user.
Let's get to the code: