A firewall is a network security device that monitors incoming and outgoing network traffic and assesses whether specific traffic should be allowed or blocked. It acts as a gatekeeper by detecting and preventing unwanted traffic from an unidentified source. It manages network traffic to help safeguard your network and information. A firewall acts as traffic by allowing the IP addresses or trusted sources to be permitted by the users. Types of firewall: Hardware Firewall and Software FirewallHardware Firewall Software Firewall Physical Non-tangible Stored between network and gateway Installed on computer Protect from the outside world. Protect from the specific device from other internal systems. The firewall used two Port numbers and applications to control data traffic. Therefore, the firewall examines traffic between a computer and a network and keep the list of IP addresses thus preventing access to certain websites. Additional Information?Attacks on personal computers prompted the development of first-generation firewalls in the late 1980s. the first stateful inspection firewall was introduced in 1993. In the early 2000s, third-generation firewalls addressed application-layer vulnerability attacks, resulting in Intrusion Prevention Systems Products (IPS). In 2017, larger-scale attacks necessitated even more sophisticated defences.