Google Plus is Google - the social layer explained!
This video gives you an overview of Google+ and how the social layer goes across so many of Google's products and services.
It includes:
Google Plus is both a social destination and the social layer
Google+ - the social destination
Gmail, related to Google+
Google Search including personalized results and Google authorship
+1 button on the website 
Google Search - an easy 'follow' link for a company with a page (so they are opting in) and you can follow your fans back!
Google Maps and Google Local e.g. reviews and Zagart, event with friends
Can link your Google+ Page to your website - driving traffic to somewhere more intimate
Google+ Page - and links into communities where you can interact with fans
Google adwords, +1s of a page (social extensions turned on) - link straight to your Google+ Page
Google Adwords - +1s on display ads, bottom of the page 
Android, inc. Google Maps 
Google Now
Play, can share with circles music for one complete play
Hangouts, (can invite circles) also using hangouts on air you can do live streams to YouTube 
Youtube - your own channel; hoosing who can 'see' your content and with whom you want to share content, sharing content generally
Drive and documents - sharing folders and collaboration with files
Calendar, and events (able to invite circles as well)
Google Wallet - showing what has been bought
Google Offers
Google Chrome 
Google Chromebook
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