Logging outgoing links
The access logs of most web servers keep detailed information about where visitors came from and how they browsed the hosted site. They do not, however, log which links visitors left by. This is because the visitor's browser has no need to communicate with the original server when the visitor clicks on an outgoing link.
This information can be captured in several ways. One way involves URL redirection. Instead of sending the visitor straight to the other site, links on the site can direct to a URL on the original website's domain that automatically redirects to the real target. This technique bears the downside of the delay caused by the additional request to the original website's server. As this added request will leave a trace in the server log, revealing exactly which link was followed, it can also be a privacy issue.
The same technique is also used by some corporate websites to implement a statement that the subsequent content is at another site, and therefore not necessarily affiliated with the corporation. In such scenarios, displaying the warning causes an additional delay.
Short aliases for long URLs
Main article: URL shortening
Web applications often include lengthy descriptive attributes in their URLs which represent data hierarchies, command structures, transaction paths and session information. This practice results in a URL that is aesthetically unpleasant and difficult to remember, and which may not fit within the size limitations of microblogging sites. URL shortening services provide a solution to this problem by redirecting a user to a longer URL from a shorter one.
Meaningful, persistent aliases for long or changing URLs
Sometimes the URL of a page changes even though the content stays the same. Therefore URL redirection can help users who have bookmarks. This is routinely done on Wikipedia whenever a page is renamed.
Manipulating search engines
Some years ago, redirect techniques were used to fool search engines. For example, one page could show popular search terms to search engines but redirect the visitors to a different target page. There are also cases where redirects have been used to "steal" the page rank of one popular page and use it for a different page, usually involving the 302 HTTP status code of "moved temporarily."
Search engine providers noticed the problem and took appropriate actions [citation needed]. Usually, sites that employ such techniques to manipulate search engines are punished automatically by reducing their ranking or by excluding them from the search index.
As a result, today, such manipulations usually result in less rather than more site exposure.
The access logs of most web servers keep detailed information about where visitors came from and how they browsed the hosted site. They do not, however, log which links visitors left by. This is because the visitor's browser has no need to communicate with the original server when the visitor clicks on an outgoing link.
This information can be captured in several ways. One way involves URL redirection. Instead of sending the visitor straight to the other site, links on the site can direct to a URL on the original website's domain that automatically redirects to the real target. This technique bears the downside of the delay caused by the additional request to the original website's server. As this added request will leave a trace in the server log, revealing exactly which link was followed, it can also be a privacy issue.
The same technique is also used by some corporate websites to implement a statement that the subsequent content is at another site, and therefore not necessarily affiliated with the corporation. In such scenarios, displaying the warning causes an additional delay.
Short aliases for long URLs
Main article: URL shortening
Web applications often include lengthy descriptive attributes in their URLs which represent data hierarchies, command structures, transaction paths and session information. This practice results in a URL that is aesthetically unpleasant and difficult to remember, and which may not fit within the size limitations of microblogging sites. URL shortening services provide a solution to this problem by redirecting a user to a longer URL from a shorter one.
Meaningful, persistent aliases for long or changing URLs
Sometimes the URL of a page changes even though the content stays the same. Therefore URL redirection can help users who have bookmarks. This is routinely done on Wikipedia whenever a page is renamed.
Manipulating search engines
Some years ago, redirect techniques were used to fool search engines. For example, one page could show popular search terms to search engines but redirect the visitors to a different target page. There are also cases where redirects have been used to "steal" the page rank of one popular page and use it for a different page, usually involving the 302 HTTP status code of "moved temporarily."
Search engine providers noticed the problem and took appropriate actions [citation needed]. Usually, sites that employ such techniques to manipulate search engines are punished automatically by reducing their ranking or by excluding them from the search index.
As a result, today, such manipulations usually result in less rather than more site exposure.