Hi
OK - so I am a bit of a social media virgin. I have a face book account but that is it - I don't use any 'apps' on it, just really read status updates. I have requested P-Interest but still haven't heard anything and this was months ago. I have signed up to twitter when I got a blackberry, but forgot the password and haven't used it since - I also just did not understand it, in the slightest
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I am posting because I have just returned to work after maternity leave, and I think I really need to get a handle on Social Media -it feels like overnight it has exploded and I am left in the dark ages squandering - but I have no idea where to start - what IS social media, what is included in social media and for example, on twitter what 'hash-tagging is'. 
Can anyone give me a recommendation for a great Janet and John website I can read - or a book?! or could some of you lovely Mnetters help me through the social media jungle and explain some terminology to me and how it works please?
Or even suggest some people I can follow on twitter so I can see how the thing works?
Thanks in advance.