Google Analytics utm_content

When I turn on the Google Analytics integration, all the links in my emails look like the following:

http://www.MyWebSite.com/?utm_medium=email&utm_source=Email%20marketing%20software&utm_content=304879939&utm_campaign=Test+Google+Analytics+_+hjljij&utm_term=Clickhere

- Can anyone help me understand what the "utm_content" parameter represents?
- Is it an identifier that uniquely identifies the recipient?
- If so, is there an API call that I can make that would allow me to retrieve additional information about the subscriber such as his name for example?

I read CampaignMonitor's documentation regarding the Google Analytics integration and it lead me to believe that this parameter would contain the recipient's email address:

Campaign Monitor automatically takes the campaign name and make it the Google Analytics utm source. Each link that goes to the domains you specified earlier will be tagged, and end up looking like this:

http://abcwidgets.cmail1.com/l/12345/l/www.abcwidgets.com/email?utm_medium=
email&utm_source=Campaign+Monitor&utm_content=[email]
&utm_campaign=ABC+Widgets+April+Newsletter&utm_term=visit+out+site

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