Dynamic DNS (DDNS) is a service that automatically updates DNS records when your IP address changes. This is essential for devices with dynamic IP addresses (which most home internet connections use) that frequently change.

Without DDNS, you would need to manually track and update your IP address every time it changes to access your home server, security cameras, or other self-hosted services remotely. With DDNS configured, the service provider's software or your router automatically notifies the DDNS server of IP changes, keeping your domain name pointed to the correct current address.

Common uses include:

• Remote access to home networks or NAS devices
• Hosting game servers from home
• Accessing security systems or IoT devices
• Running personal websites or applications

Most hosting providers and router manufacturers offer DDNS services, often with free options for basic needs. Setup typically involves:

1. Creating an account with a DDNS provider
2. Configuring your router or installing client software
3. Choosing a subdomain (e.g., yourname.ddnsprovider.com)

Remember that while DDNS solves the changing IP problem, you still need to configure proper port forwarding on your router and ensure adequate security measures for any services you expose to the internet.