Server access logs contain raw (text-based) information about each request made to your web site. Every time a visitor calls up, or opens, one of your pages, a few requests are commonly made to the server when the visitor's browser asks the server to provide the HTML file, images, audio files, and other page elements. Each server request will be listed in your access log.
Here are a few sample lines of a site's access logs:
216.145.57.229 - - [05/Mar/2002:12:07:04 -0800\ "GET /examples/ HTTP/1.1" 200 1274 "http://webmaster-showcase.net/" "Mozilla/4.0 (compatible; MSIE 5.5; Windows NT 5.0)" "webmaster-showcase.net"
216.145.57.229 - - [05/Mar/2002:12:07:05 -0800\ "GET /images/webmaster-showcase.net.png HTTP/1.1" 304 - "http://webmaster-showcase.net/examples/" "Mozilla/4.0 (compatible; MSIE 5.5; Windows NT 5.0)" "webmaster-showcase.net"
216.145.57.229 - - [05/Mar/2002:12:07:05 -0800\ "GET /images/HOME.png HTTP/1.1" 304 - "http://webmaster-showcase.net/examples/" "Mozilla/4.0 (compatible; MSIE 5.5; Windows NT 5.0)" "webmaster-showcase.net"