These are files that are constantly and automatically created and updated on your web server. They provide very specific details about the activities taking place on your web site. Log Files include URLs, IP addresses, pages visited, errors generated, number of unique visitors, total page views, total hits and other pieces of information. When carefully reviewed they throw a lot of light on the performance and visitors to the site.
a text record of activity for a certain web account over a specified period. Logs record various information about your visitors... time of visit, ip address, the referring site, visitor's browser type and other helpful statistical stuff. .