• A firewall is a network security device that analyses incoming and outgoing network traffic and determines whether specific traffic should be allowed or blocked based on a set of security rules.
• For more than 25 years, firewalls have served as the first line of defence in network security. They create a barrier between secure, controlled internal networks that can be trusted and untrustworthy external networks like the Internet.
• A firewall can be hardware, software, or a combination of the two.
• A firewall is a network security device that monitors and regulates incoming and outgoing network traffic according to specified security rules in computing. A firewall is a device that separates a trusted network from an untrusted network, such as the Internet.

Read More: What is NIC?