Suggest an edit

Improve this article

Refine the answer for “What is a network in Docker?”. Your changes go to moderation before they’re published.

Approval required

Content

What you’re changing

Title (EN)

Short answer (EN)

Shown above the full answer for quick recall.

Answer (EN)

A network in Docker is a mechanism that lets containers **talk to each other** and to the outside world. Docker creates isolated virtual networks where each container gets its own IP address and can securely interact with other services.

What this gives you:

## Isolation

Containers in the same network see each other, while containers in another network do not. This improves security and manageability.

## Communication by service name

Inside a Docker network, containers can reach each other not by IP, but by service name:

```javascript
http://db:5432
```

## Built-in DNS

Docker resolves service names inside the network itself, nothing needs to be configured manually.

Example in `docker-compose.yml`:

```yaml
services:
  app:
    image: myapp
    networks:
      - internal_net
  db:
    image: postgres
    networks:
      - internal_net

networks:
  internal_net:
```

The `app` and `db` containers end up in the same `internal_net` network and can communicate with each other.

**Summary:** a network in Docker is a virtual environment in which containers exchange data. It provides isolation, convenient interaction, and automatic DNS inside the environment.

Markdown · drag & drop images · ⌘B / ⌘I shortcuts169 words

For the reviewer

Note to the moderator (optional)

Visible only to the moderator. Helps review go faster.