A firewall is a network security device or software that acts as a barrier between a trusted internal network and untrusted external networks, such as the internet. Firewalls monitor and control incoming and outgoing network traffic, enforcing security policies and protecting against unauthorized access, cyberattacks, and data breaches.
Firewalls use rules and filters to inspect data packets and determine whether they should be allowed to pass through the network or be blocked. For example, a company's network may use a firewall to prevent unauthorized access to sensitive corporate data and to filter out malicious traffic, such as viruses and malware.
