Before any device can communicate on the internet, three fundamental services work behind the scenes. DNS translates human-friendly domain names like google.com into machine-readable IP addresses so your browser knows where to send requests. DHCP automatically assigns IP addresses to devices joining a network, eliminating the need for manual configuration. NAT allows multiple devices on a private network to share a single public IP address by rewriting packet headers as traffic crosses the boundary. Together, these three protocols form the invisible foundation that makes seamless internet connectivity possible for billions of devices worldwide.