Indeed. Traffic served from 0.0.0.0 can be seen from other machines. Traffic on 127.0.0.1 or localhost cannot. Important to know when you’re doing local development vs a local demo.

IP addresses with 0 as the first octet are invalid and hopefully will not be routed. I prefer them for hosts files over localhost because localhost has to wait and time out, but 0.0.0.0 will fail right away.

Not sure why Ive been downvoted. I’ve used this all the time for demoing projects. It’s like asking for port 0. You don’t get the actual 0.0.0.0 IP address, but you use a physical network instead of the loopback virtual network device. Heck; I’ve had to change this in web hosting projects as a security vs feature trade off.