The interesting part about Google and Facebook is that these super giants didn’t even exist a couple of decades ago. Google was created by two guys from their university dorm room, and Facebook started in basically the same way. Just take a look at this screenshot of Facebook from 2005 (7 years ago):
and Google from 1999 (13 years ago):
These sites, employ thousands of people (33,000 employees currently work at Google and 3,000 for Facebook) and get billions of hits from users. For me the amazing thing is that beneath the hood, the code which makes up the core of their functionality is really just a tweaked and improved upon version of what Zuckerberg, Brin and Page came up with in their free time.