input: [Provider] Google Analytics [Name(s)] _ga [Expires] 2 years [Purpose] 
output: This cookie name is associated with Google Universal Analytics - which is a significant update to Google's more commonly used analytics service. The new service reduces the reliance on cookies in general, and only sets this one, although Google also say data can be collected without setting any cookies. This cookie is used to distinguishes unique users by assigning a randomly generated number as a client identifier. It is included in each page request in a site and used to calculate visitor, session and campaign data for the sites analytics reports.