A default gateway serves as an access point or IP router that a networked computer uses to send information to a computer in another network or the internet. It is essentially the forwarding node that routes traffic from a local network to other networks. When an IP packet's destination is not within the local network and no specific route is defined in the routing table, the packet is sent to the default gateway. Reference: Cisco DevNet Associate Certification Guide: Chapter on Networking Basics and Routing Fundamentals. Cisco Documentation on Default Gateway and Routing.