By Configuring inter-VLAN routing on a Cisco router, it allows devices on different VLANs to communicate with each other. This is typically achieved using a "router-on-a-stick" configuration where a single physical router interface is used to route traffic between multiple VLANs via subinterfaces.
This video demonstrates the setup of inter-VLAN routing using a router and Layer 2 switch in Packet Tracer: