# How to Use Docker Compose
## Purpose
Learn how to define and manage multiple Docker containers using a simple YAML configuration file with Docker Compose.
---
## 1. Install Docker Compose
If you don't already have Docker Compose installed, install it:
```bash
sudo apt update
sudo apt install docker-compose-plugin -y
```
---
## 2. Create a Docker Compose File
Create a directory for your project and add a `docker-compose.yml` file inside it:
```bash
mkdir my-project
cd my-project
nano docker-compose.yml
```
Example `docker-compose.yml`:
```yaml
version: '3'
services:
web:
image: nginx
ports:
- "8080:80"
```
---
## 3. Start the Application
Use Docker Compose to bring up your containers:
```bash
docker compose up -d
```
*The `-d` option runs it in the background (detached mode).*
---
## 4. Stop the Application
When you want to stop and remove all containers defined in the Compose file:
```bash
docker compose down
```
---
## ✅ Summary
- **Compose simplifies** multi-container deployments with a single file.
- **Use volumes** inside `docker-compose.yml` to persist your data.
- **Keep your Compose files** under version control (like Git) for easy recovery and updates.