This site does not aim to collect or retain personally identifying information about users.  There may be a limited use of cookies – small text files that are placed on your machine to help the site provide a better user experience. In general, cookies are used to retain user preferences – for example, remembering whether you have already confirmed acceptance of our privacy policy, and to provide anonymised tracking data to third party applications like Google Adsense, which provides advertising to support the website. As a rule, cookies will make your browsing experience better. However, you may prefer to disable cookies on this site and on others. The most effective way to do this is to disable cookies in your browser. We suggest consulting the Help section of your browser or taking a look at Cookies and You, which offers guidance for a range of browsers.