It's the age old debate, closed ports verses stealthed ports. First, what is a port? A port is the door to your computer, there's different ports for different things. The three-way handshake takes place, and the information is then delivered to your computer to a certain port, and the information is then received. But we can save that for another topic. Now, the age old question is would you like your ports to show up as being closed, or as being stealthed? My own opinion is that I prefer stealthed over closed. If someone probes your computer would you rather them see ALL of your ports as being "CLOSED"? Or would you rather them probe and see nothing? I prefer stealthed just because if someone probes me I'd rather them see nothing, it makes it as if I don't exist, it's like someone knocking on the door and me not answering or even acknowledging. But then again if they see "CLOSED" they know you exist but they know your ports are closed and there really isn't much they can do. The fact they now know you exist though means they can not only probe you, but they can do more malicious damage by knowing your internet protocol exists like knocking you offline with a denial of service or anything else. Although really the only difference between stealthed or closed is that when 'so and so' application taps your firewall and hits a closed port it will stop. If it sees it's 'stealthed' it'll continue to try and try and try to connect to a port that isn't there, which is wasting bandwidth(although small) and taking up connections overhead.In summary, users should be much less worried about how they "look" to the evil outside, because it is irrelevant. The real differences occur in problems to their own internet activities directly caused by a misguided belief in "stealth at all costs". This is just a summary and the article could be very much larger but this is just a small summary of closed and stealthed ports.