Final answer:
A demilitarized zone (DMZ) is a network segment between an internal network and an external network, providing an additional layer of security. It contains servers that need to be accessed by users outside of the internal network.
Step-by-step explanation:
In the context of a web server between two firewalls, a demilitarized zone (DMZ) is a network segment that is placed between an internal network and an external network, typically the internet. It acts as a buffer zone and provides an additional layer of security by segregating the internal network from the external network. The DMZ contains servers that need to be accessed by users outside of the internal network, such as web servers, email servers, and FTP servers.