I had an interview at a relatively secure place. Premises are walled and gated, the first thing you come to is a checkpoint with armed guards and security cameras. If you don't have an access card or your access card isn't permitted in the area you're going to, you don't go in without escort. And that escort must have been agreed to in advance; the security team must have a document about your planned trip. Of course they check your id before calling the escort. People don't do work on internet connected computers; if you need to browse, there's a separate computer for that. That's about as much I'm comfortable revealing.. it goes deeper :)

I guess it's a place where "getting work done" doesn't involve downloading 1000 deps with npm and what have you from random sources on the internet.