It is very important for every website owner to collect information about visitors, their behavior, how they move on the website, which interests the have and how long time they spend on which pages. Web servers collect information and save them in log files.
However, outgoing links on your web site can really hurt your google rankings. Search engines such as Google don’t make you responsible for links found over the web linking to your website but they do make you responsible for links found on your own website. If you link to a banned or dead website, you risk losing ranking ranking position in the search engine results.
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SEO Killer Server Log Files