How can a non-geek set up a proper firewall?

Question

Maybe a non-geek that knows of the existence of a firewall is already some kind of a nerd. If you have been a windows-user then it was rather easy to set up a firewall (I don't know if it was a good one!): enable a firewall with maximum protection. Then for each program that tried to make an internet-connection a notification was shown (allow or not allow). In this way without any prior knowledge of protocols and ports a user could set up a firewall that was suited to his needs. Is there any equivalent program in Ubuntu so that any user can set up a proper firewall?

Answer 1

gufw

gufw is an easy and intuitive way to manage your Linux firewall. It supports common tasks such as allowing or blocking preconfigured, common p2p, or individual port(s), and many others. To install gufw in all currently supported versions of Ubuntu open the terminal and type:

sudo apt install gufw

Answer 2

Firestarter

sudo apt-get install firestarter

Answer 3

If you are using a router, and you have not disabled it then you most likely are behind a what they refer to as a "hardware firewall", for most users this is fine...