Final answer:
Devices use Network Address Translation (NAT) to communicate on the internet with a private IPv4 address, allowing multiple devices to share a single public IP address.
Step-by-step explanation:
A device can be configured with a private IPv4 address but communicate on the internet using a globally routable IPv4 address through a mechanism known as Network Address Translation (NAT). NAT is used by routers to translate private, non-routable IP addresses within a local network to a single public IP address before sending traffic out to the internet. This allows multiple devices on a local network to share a single public IP address, which is essential due to the limited number of available IPv4 addresses.