Final answer:
Address translation on networks is crucial for routing traffic correctly, conserving IP addresses, and providing security by hiding internal network structures.
Step-by-step explanation:
Address translation on networks is necessary for various reasons. It enables the routing of traffic across the internet and within local networks, ensuring that data packets reach their intended destinations. Address translation also provides a way to conserve the number of IP addresses needed, which is important given the limited availability of IPv4 addresses. Moreover, address translation adds a layer of security by obscuring internal network structures from the public internet. Network administrators use address translation to help manage the network efficiently, maintaining control over network traffic and access.