# Docker Networks

**Networks** allow containers to communicate. By default, containers on the same network can reach each other by service name. Create custom networks for isolation; bridge networks are best for most use cases. Compose automatically creates a shared network for all services.

```bash
$ docker network create mynet         # create a bridge network
$ docker run --network mynet myapp    # attach a container to the network
$ docker network connect mynet <id>   # add running container to network
$ docker network ls                   # list networks
$ docker network inspect mynet        # inspect network details
```

Containers on the same network resolve each other's service name via DNS, so you can `ping myapp` from another container without knowing its IP. The default `bridge` network has limitations—use custom networks for better service discovery. You can also use `host` networks (container uses host's network directly) or `overlay` networks for swarm mode.