It is a stats package for websites. You add a little code to your site and it gives you tons of information on your visitors and traffic.
You have to install Awstats on your webserver, while you dont have to install Analytics on your web server, just place a snippet of code on the webpages you want to track. And sure it provides more info in a better way than any other stats checker.
Nice, although i am not a fan, but i need the thing for one of my site is on plesk and no awstats available and its pretty hard to track the traffic on that site. So if u got option to send invite let me know if u dont intend to use it