# Exposing Ports — Docker

Source: https://www.geekswithgeeks.com/en/docker/docker-exposing-ports

> Map a container's internal port to a port on your host machine.

## -p host:container

By default a container's network is isolated. `-p 8080:80` forwards your host's port 8080 to the container's port 80.

```bash
docker run -d -p 8080:80 nginx
# visit http://localhost:8080 on your host
```

## EXPOSE is just documentation

The Dockerfile's `EXPOSE 80` instruction only **documents** the intended port — it doesn't actually publish it. You still need `-p` at run time.