“Hello World” is the name for the most basic program that a programmer will write when learning a new language or a new programming platform. It generally consists of the application doing nothing more than displaying the text “Hello World” on the display device supported by the platform, be it a web page, a console, a printer, a cell phone screen, a Window on a Mac, Windows, or Linux box.
This is standard practice for programmers and is expected in tutorials for programmers for new platforms and languages.