Answer Description
Network Address Translation (NAT) hides the internal IP, but also is used to conserve IPv4 addresses, by using one IP address for the entire private network.
Wikipedia
Network address translation (NAT) is a method of remapping an IP address space into another by modifying network address information in the IP header of packets while they are in transit across a traffic routing device The technique was originally used to avoid the need to assign a new address to every host when a network was moved, or when the upstream Internet service provider was replaced, but could not route the networks address space It has become a popular and essential tool in conserving global address space in the face of IPv4 address exhaustion One Internet-routable IP address of a NAT gateway can be used for an entire private network
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