I was surfing the Net tonight and my Norton firewall came up with a message saying that an intruder had been stopped trying to get into my computer. Now, I'm kind of new with this security stuff. Norton told me that the attack was a "portscan". So what I need to know is exactly what is a portscan, and how much of a threat is it? I ran the IP address from the offending computer on this site, and it came back to somewhere in France. It didn't give an ISP or anything like that. The trace didn't get more specific than the country. So, do I have anything to worry about here?