Glossary: ASP.NET Core

Host addresses (127.0.0.1, 0.0.0.0)

Also written: 127.0.0.1, 0.0.0.0, localhost

`127.0.0.1` is the address of this computer itself (what `localhost` means), reachable only from that machine. `0.0.0.0` as a listen address means every network connection on the machine, so other computers can reach the app.