I was wondering about how obscure old files such as images [0] can remain on massive sites like google.com or facebook.com [1] for so long? Surely after enough server migrations and rewrites, they'd get lost somewhere?Google is still hosting an assortment of logo ideas, including one from when it was called Backrub!? [2]How does this happen? After 2 decades, how and why are these old files still accessible on the web? Is some of Google's ancient infrastructure still running somewhere? Is that even possible?[0] 
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