I had no idea that “.io” referred to a place and not just “input/output.” Learned a lot from this one.

[…] .io is also a place: a country-code top-level domain, or ccTLD, which refers to a particular place on the Earth’s surface. In this case, that place is the British Indian Ocean Territory, a remote but strategically-important scattering of islands in the middle of the Indian Ocean, also known as the Chagos Archipelago.

via The story of .io | Citizen Ex. (hat tip: David A. Kennedy)