If the author states that there are already a number of Hello World examples, why not spend a bit more time and create something else that's still simple enough?

As a self-taught programmer, one of the difficulties I found (before SO) was that the many articles one read up on would typically repeat what someone else said. This especially with new technologies.

I think if authors pointed us to an existing "Hello World", and then expanded on that, in the long-run, beginners would sometimes find it easier to learn fadter.