Is It Really GPS If It Doesn't Use Satellites?
The answer is no. No it is not GPS If it doesn't use satellites. In fact, even if it does use satellites, it's not GPS unless it uses the data received by the USA DOD GPS satellite transmitters. GPS is a pronoun, a proper name. GPS refers to, specifically and explicitly, the DOD GPS satellite system and anything not relying on the signals transmitted by those specific satellites IS NOT GPS.
HTML, XML, and really the whole SGML family kind of suck-- ugly syntax, annoying to hand-edit, lots of boilerplate, and the list of faults go on. The idea of writing actual programs in such a language is terrifying.
You cannot write programs in any of those. They are not programming languages. They are markup languages. That's why they all have ML in each acronym. It's short for "Markup Language".
"Anyone attempting to generate random numbers by deterministic means is, of course, living in a state of sin." -- John Von Neumann