A router in a computer network is a device that connects two or more networks, such as local area networks (LANs) or wide area networks (WANs), and forwards data packets between them. It acts as a gateway that directs traffic, using Internet Protocol (IP) addresses to determine the best path for data to travel from the source to the destination across different networks

. Key functions of a router include:

• Receiving data packets from devices on one network and sending them to the appropriate device on another network by examining the destination IP address in each packet

• Managing traffic between networks to allow multiple devices to share the same internet connection and communicate with each other, even without internet access

• Using routing tables, which contain rules and paths, to decide the optimal route for forwarding packets

• Performing Network Address Translation (NAT) to enable multiple devices on a private network to share a single public IP address, enhancing security and conserving IP addresses

• Filtering packets to block suspicious traffic and prioritizing certain types of data using Quality of Service (QoS) mechanisms

Routers can be physical hardware devices or virtual software instances. Home routers often combine multiple functions such as routing, wireless access point, and switching in one unit, while enterprise routers are more sophisticated and handle large-scale network traffic at high speeds

. In summary, a router is an intelligent network device that directs data traffic between different networks, ensuring efficient and secure communication across the internet or private networks