Tutorials > How a firewall works

What is a firewall

First of all it is important to understand in basic terms what a firewall is. In agricultural terms a firewall is a piece of land, normally a pretty wide dirt road, that would not allow a fire in one field to move and set on fire the next field, due to the fact that a dirt road has no parts (like leaves or dry wood) that can "carry" the fire.
In computer terms a firewall is a system (either hardware based or software based) that divide, actually isolate the two fields, one being the external world ie. the Internet, and the other, the internal world or computer or computer network.

Opening a number of ports in the firewall, we can allow information to go from the internet to our network (inbound traffic) or from our computer or network outside (outbound traffic).
 

Controlling the packets of data that goes thru a firewall, allows to block potential hackers to infiltrate your network and also to control in both directions the use of the internet connection.