unique visitors - ip or host?

[Johan]

Hi,

how do most scripts determine whether a visitor is unique or not? Do they track the ip or the hostname of that visitor?
(determining whether i will buy a script or make one myself)

Thnx,
Joe
www.ineedfreesex.com (http://www.ineedfreesex.com)

[andy2000]

I think it's the ip

[ProgGod]

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