What does this message on my computer mean?

ok so i got this message last night on my computer and it told me something like my IP address matched another IP address on the website i was on or something really close to that. ive never seen this message before. i have norton anti virus on my computer and im running a virus scan i just want to know what this means. is someone trying to hack into my computer or something? is this going to affect my computer in anyway?