What does the Webmaster know about you?

Almost all web sites maintain logs of the their activity. Here are two entries from the access log on my web server:

206.231.104.139 - - [12/May/1997:11:50:11 -0700] "GET /public/nearest.html HTTP/1.0" 200 3156
206.231.104.139 - - [12/May/1997:11:50:24 -0700] "GET /public/bright.html HTTP/1.0" 200 3827

A user, unidentified here, came in from machine at 206.231.104.139.
The user asked for nearest.html and we sent it out.
Then the user asked for bright.html, which was also sent.
The user then left this site.

Here is an entry from the error log:

[Mon May 12 16:28:54 1997] access to /u8/WWW/personal/diplas/jwz/diplas1.html failed for polypc21.chem.rug.nl, reason: File does not exist

Other information could have been captured depending on what you have set up/filled in on your browser.
In addition, the provider's server interacts with your browser. It may request and you may permit the passage of cookies back and forth. These cookies are really bits of information about the sites you visit and what you look at. These are used for tracking purposes, but may carry information such as username and password for some commercial sites.