Interpreting Web Server Log Files
An abundance of log analysis software is available for Unix operating systems (and thus Tiger). Log analysis is more of an art than a science. As you've seen by looking at the log file formats, you can determine the remote host, requested resource, and time of request from the log file. Unfortunately, many analysis packages try to go even further by providing information on how long visitors were at your page, or where (geographically) they are located. Neither of these pieces of information is tracked in the Apache logs.
Understanding Web Statistics
To determine how long someone has been at your site, the analysis software must look at all accesses and determine which are related, and the amount of time between ...