How do IP address lookup websites get their information?

Websites like www.ipaddresslocation.org and www.find-ip-address.org are able to give the correct city of an IP address over 90% of the time and even the correct neighborhood at least half of the time? Do these websites get their lists from Internet providers or do they have some sort of algorithm? Is this legal?|||Lets take a random hypothetical ip of 77.127.7.7





The 77 is the class A ISP (The main *backbones* of the internet...these people give out domains to other people)





127 is a class B address (Closing in Geographically to a *regional* service provider, these people are your ISP's that give internet out to other people)





7 is your network (Every computer on your network will have an ip that is 77.127.7.X)





and the final 7 is your physical computer





By taking an IP address and tracing its path through a ping, you can geographically zone in on a computer; but these results are skewed, as it will only give you an *area* not an address.





And yes, its legal.|||I suggest you learn about IP addresses instead of subscribing to the general paranoia so rife at the moment. I see questions on here like, "This guy told me he has my IP address, I'm scared. What should I do?"





The site http://whatismyipaddress.com/ gives my IP address as 122.59.75.223.


www.ipaddresslocation.org gives some detail about my browser and ISP but cannot identify me.|||They probably have good IP location database and use some advanced tracking techniques.


Another good website is http://www.ip-address.org|||l