What is the purpose of NAT (Network Address Translation) in networking?

Network Address Translation (NAT) is a technique used to hide internal network addresses from external networks. It allows multiple devices within a private network to share a single public IP address when communicating with external networks, such as the internet. NAT operates at the network layer of the OSI model and translates private IP addresses to a single public IP address when outgoing packets leave the internal network. This translation helps improve security by masking the internal topology of the network, preventing direct access to internal devices from external sources. Additionally, NAT conserves public IP addresses by allowing multiple devices to access the internet through a single public IP address.