Redirects are accomplished using the 301 and 302 status codes. Heres an example of the HTTP headers in a 301 response.
HTTP/1.1 301 Moved Permanently
The browser automatically takes the user to the URL specified in the
Location field. All the information necessary for a redirect is in the headers. The body of the response is typically empty. Despite their names, neither a 301 nor a 302 response is cached in practice unless additional headers, such as
The main thing to remember is that redirects slow down the user experience. Inserting a redirect between the user and the HTML document delays everything in the page since nothing in the pageRead More »from High Performance Web Sites: Rule 11 Avoid Redirects