For those that have never been in one. Those pics really don't due any justice. Vids would have been better. Datacenters are cold and they are loud. Those qualities just don't come across with pics.
Several of our customers thought about building their own largish datacenter in some unused commercial spaces they own. While they often had some idea about requirements of electricity and connectivity, not a single one thought about the incredible noise coming from all this hardware (or HVAC requirements, for that matter).
Loud, cold/hot. With the trends to making PUE count it can get quite uncomfortable in a hot aisle. The inefficient ones are more sweater territory...