0.0.0.0 has a couple of different meanings, but in this context, when a server is told to listen on 0.0.0.0 that means "listen on every available network interface"., In short, 0.0.0.0 is a non-routable address that describes an invalid or unknown target. However, it means something different depending on whether it's seen on a client device like a computer or on a server machine., 127.0.0.1 is the loopback address (also known as localhost). 0.0.0.0 is commonly used as a non-routable meta-address used to designate an invalid, unknown or non applicable target (a no particular address placeholder). However this is non-standard and possibly in conflict with RFC 1122., Have you ever seen the 0.0.0.0 address and wondered what it means? This is a special IP address that represents all interfaces on a machine. In this blog post, we will discuss what the 0.0.0.0 address is used for and how to interpret it!, In the context of interface binding, the address 127.0.0.1 means that the server only listens to the loopback interface. On the other hand, binding our server to the 0.0.0.0 interface means we want to accept traffic from all of the available interfaces. Let’s look at an example., .