The primary function of a router on a network, such as the internet, is to facilitate the transfer of data packets between different networks. It determines the most efficient way for data to travel from its source to its destination by forwarding packets based on information contained in their headers, such as IP addresses. Routers ensure that data reaches the correct destination by establishing and maintaining a routing table that contains information about various networks and their interconnected paths. Moreover, routers can perform functions such as network address translation (NAT), firewalling, and quality of service (QoS) management.
