Youngsters. I started in HTML at 16.
Well, if we start to count on that; we'd have to say then;
1- HTML is not a programming language; as refered in its name, its just a mark-up language.
3- CSS is not a programming language either; see the name again..
4- AJAX is definitly not a language, it's better called a set of JS methods and libraries.
Accordingly the only programming language counted in the list is PHP; besides it's being counted in scripting languages at some places.
Whatever, I guess our young friend has a long way to go; but being eager and having enough opportunities he's getting fast to where he likes. Still worth to appreciate though.