1. If you run Google Analytics on your web site, up to 4 cookies are stored in your browser.
2. UK law now states:
Cookies or similar devices must not be used unless the subscriber or user of the relevant terminal equipment:
(a) is provided with clear and comprehensive information about the purposes of the storage of, or access to, that information; and
(b) has given his or her consent.
(Text from [here] on the Information Commissioner's Office (ICO) web site)
Adding these two together, it means that if you run a web site with Google Analytics in it, you'll need to tell your user, and you'll need to obtain his / her consent
Fortunately, the ICO's web site tells us "Implied consent is a valid form of consent and can be used in the context of compliance with the revised rules on cookies". But it warns "If you are relying on implied consent you need to be satisfied that your users understand that their actions will result in cookies being set. Without this understanding you do not have their informed consent."
I've been looking into the Google Analytic Cookies in order to provide our users with the required clear and comprehensive information that's required.
If you use Google Analytics on your web site, there are four different cookies they may set in your browser, and at least one of those cookies will initially be set the first time that a new user visits a page into which you have inserted the Google Analytics code.
a) __utma - a cookie which is persistent. Set on a visitor's first logged visit to your site, it says to Google "it's me again" on each subsequent visit to a logged page
b) __utmb and __utmc - a pair of cookies with a short life which help Google work out how long your visitor remains on each page
c) __utmz - provides information to track where a visitor arrived from on their current visit (seach, bookmark, etc)
d) __utmv - will only be set if you have configured your Google Analytics to allow for custom segmentation of your visitors in some way.
I'm not sure how much detail we need to go into telling our users about each of these cookies. I am choosing to use the following text on our sites:
We use Google Analytics on this site, so that we can track site usage overall, and analyse the results to learn more about the general profile of our visitors (but not any one visitor in particular), for the purpose of learning about trends, the relative importance of pages, about where our visitors come from, how long they stay, what technlogy they're using, and so on. The purpose of learning about this data is to help us improve the service we offer, and to spot any changes in usage pattern and react accordingly. Google Analytics places cookies in your browser for this purpose.
And where practical to provide an example of some ot the reports generated:
Diagram from Google Analystics showing the number of visitors per hour through a week.
Diagram from Google Analystics showing general statistics for the last week
Map / Diagram from Google Analystics showing the locations of UK visitors to this site in the last week.
These sample diagrams are from our First Great Western Coffee Shop Forum
, for the 7 day period ending on 1st June 2012. (written 2012-06-02)
Associated topics are indexed as below, or enter http://melksh.am/nnnn for individual articlesG911 - Well House Consultants - Search Engine Optimisation 
Implementing an effective site search engine - (2005-01-01) 
The Melksham train - a button is pushed - (2005-08-28) 
Search engine placement - long term strategy and success - (2006-12-30) 
Our search engine placement is dropping. - (2007-01-11) 
Catching up on indexing our resources - (2007-09-10) 
Which country does a search engine think you are located in? - (2008-09-11) 
Search Engines. Getting the right pages seen. - (2009-01-01) 
Telling Google which country your business trades in - (2009-01-02) 
Cooking bodies and URLs - (2009-01-08) 
Site24x7 prowls uninvited - (2009-01-10) 
2000th article - Remember the background and basics - (2009-01-18) 
Baby Caleb and Fortune City in your web logs? - (2009-01-31) 
Does robots.txt actually work? - (2009-02-16) 
Static mirroring through HTTrack, wget and others - (2009-03-03) 
Learning to Twitter / what is Twitter? - (2009-03-28) 
How to tweet automatically from a blog - (2009-03-28) 
Reaching the right people with your web site - (2009-04-23) 
What search terms FAIL to bring visitors to our site, when they should? - (2009-08-05) 
Update - Automatic feeds to Twitter - (2009-08-09) 
Diluting History - (2009-09-27) 
Web site traffic - real users, or just noise? - (2009-12-26) 
Tuning the web site for sailing on through this year - (2010-01-03) 
Freedom of Information - consideration for web site designers - (2010-03-20) 
Monitoring the success and traffic of your web site - (2010-05-01) 
Reading Google Analytics results, based on the relative populations of countries - (2012-03-24) 
Has your Twitter feed stopped working? Switching to their new API - (2013-06-23)A213 - Web Application Deployment - Commercial and Legal Aspects 
Colour for access - (2004-12-06) 
Responding to spam - (2005-03-27) 
Colour blindness for web developers - (2005-04-22) 
Ordnance Survey - using a 'Get a map' - (2005-05-22) 
More maps - (2005-05-23) 
Copyright - how much can I legally copy? - (2005-12-17) 
Domain Listing Center and Domain Registry of America - (2006-06-06) 
Watch your Google profile - (2006-06-13) 
Remember a site's non-technical issues too - (2006-07-07) 
Making pages clearer - easy Disability Discrimination Act Compliance - (2006-09-23) 
Training on Cascading Style Sheets - (2006-12-17) 
UK legal requirements for your commercial web site - (2007-01-27) 
Getting the community on line - some basics - (2007-11-13) 
Copyright and theft of images, bandwidth and members. - (2007-12-26) 
Does anyone understand Lithuanian? - (2007-12-27) 
Ongoing Image Copyright Issues, PHP and MySQL solutions - (2008-01-14) 
Who is watching you? - (2008-08-10) 
Validating Credit Card Numbers - (2008-10-14) 
Getting hold of the wrong end of the stick - (2008-12-12) 
Beware - giving copyright away when you upload a picture - Dogs Trust - (2009-04-25) 
Leaping dog, Leaping horse, copyright of old masters - (2009-06-20) 
Re-using our pictures - (2010-01-21) 
The legal considerations of your web presence - revisited - (2010-10-26) 
Catering in Syracuse, the Saigon Cafe, stolen images and Christmas - (2010-12-25) 
Web Sites - Subject to Advertising Standards from 1st March - check your sites - (2011-02-13) 
An easy way to comply with the new cookie law if your site is well designed - (2012-06-02) 
Change to Libel and Defamation laws from 1st January 2014 - (2013-12-31) 
Can a legitimate forum post become illegal a year later? - (2014-07-11)
Some other Articles
Matching opening hours to when customers can come in and buyRemoval of water safety equipment, and how to use a lifesaver ringNot everyone has a computer - 9 more ways to learn about the Melksham CampusGoogle Analytics and the new UK Cookie law Short Web Addresses for MelkshamSunday - no longer a day of restDysenni Valley, and nearbyLow carbon and other environmental lessons for the Melksham Campus?