@ntnsndr and then there are web archiving practices, which is an area I'm specifically studying as a PhD student. The huge force here is the Internet Archive who have been working on nothing short of archiving the entire web. If this sounds like a crazy idea it kind of is, but it's more of an aspirational goal than what is actually happening. There are also organizations around the world that archive web content, a lot of which (but not all) is open. https://en.wikipedia.org/wiki/International_Internet_Preservation_Consortium