Are you in the right section? Because the generic term Community Sharing refers to non-profit or charitable events, where food, clothes and other help is distributed to the less fortunate. Now, if we are speaking about SEO, I believe you might be referring to social mesia sharing, which basically is exactly what it says - distributing your content, articles, promotions etc. in the social media channels - Facebook, Twitter, Pinterest and the likes. Hope that sheds a little light