Angular2 is a completely different library than the old version, so different that there's some question whether it should even be called Angular. Angular2 has a radically different, much improved, architecture and syntax, is easier to use, and is much faster. Though Google is committed to continue its support for Angular 1 for the foreseeable future, Angular2 is the path forward. You should use it in new applications.
The class focuses on Angular itself; we will not spend time building a web server, for example.