A script may not be what your looking for, but this one provides a lot of info. Its Page Count plugin can monitor individual page hits so you can see what pages most people are interested in. (It's more than just a counter, and can be invisible.)
http://ekstreme.com/phpcounter/
If using a web host, it may have some statistics you can view. If you are hosting your site locally yourself, I personally can't help you there. Thought I'd share that script just in case.
Hello,
what software should I use to monitor the traffic to my website?
Regards,
Mirza

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