what does a firewall do
A firewall is simply a program or hardware device that filters the information coming through the Internet connection into your private network or computer system. A firewall trusts nobody unless it is told otherwise.It secures your computer from the outside world.It helps protect computers inside a large company. firewall gives a company tremendous control over how people use the network. A firewall examines all traffic routed between the two networks to see if it meets certain criteria. If it does, it is routed between the networks, otherwise it is stopped. A firewall filters both inbound and outbound traffic.