What is a firewall?
Firewall is a common name for a software or hardware barries to protect unauthorized access from the network to the computer or other network device.
All firewalls, commonly, works like filters for inbound and outbound traffic. Them also provide functionality, which allows to set-up various options, like allow/deny the incoming/outgoing connections to a specific port numbers. Them also could provide another functionality for traffic management and are possible to produce security alerts, etc.
Functionality of the firewalls differs from vendor-to-vendor, but the major their job is a traffic filtering and preventing unauthorized access to the device, subnetwork or local resources.
Thus, for today a PC, not protected by a firewall, by statistics, will be injured by viruses in several minutes. So it is highly recommended setup and use a firewall on your personal computer. Today almost all modern operating systems include a firewall software by default. So we recommend, at least, using a built-in in your OS firewall. For example, Windows includes Windows Firewall. In Linux systems, the most well-known is Iptables.
We also recommend checking your firewall settings and see if your PC or home network is vulnerable to the outside network attacks, by checking for opened ports with our port scanner.