How We Use Cookies

We sometimes place small data files on your computer. These are known as cookies. Most websites do this.

Our cookies aren't used to identify you personally. They're just here to make the site work better for you. Indeed, you can manage and/or delete these small files as you wish.

To learn more about cookies and how to manage them, visit

Measuring website usage (Google Analytics)

We use Google Analytics to collect information about how people use this site. We do this to make sure it's meeting its users' needs and to understand how we could do it better.

Google Analytics stores information about what pages you visit, how long you are on the site, how you got here and what you click on. We do not collect or store your personal information (e.g. your name or address) so this information cannot be used to identify who you are. We do not allow Google to use or share our analytics data.

The following cookies are set by Google Analytics:

_utmaThis randomly generated number is used to determine unique visitors to our site2 years
_utmbThis randomly generated number works with _utmc to calculate the average length of time users spend on our site30 minutes
_utmcThis randomly generated number works with _utmb to calculate when you close your browserwhen you close your browser
_utmzThis is a randomly generated number and information about how the site was reached (e.g. direct or via a link, organic search or paid search)6 months
GDS_successEvents GDS_analyticsTokensThese cookies help us identify how people use so we can make the site better4 months

You can opt out of Google Analytics cookies on all sites by visiting this page on Google.

Cookies from YouTube

On some parts of this site, we use YouTube to provide useful videos. YouTube sets some or all of these cookies when you visit one of these pages.

_use_hitboxThis is a randomly generated number that identifies your browserwhen you close your browser
VISITOR_INFO1_LIVESet when viewing a page with Youtube videos on it. It is set by Youtube so they can count the views of embedded Youtube videos on them9 months