Community Sites are new in SharePoint 2013.
They provide forums for people to ask and answer questions, post information, comment on posts and get rewarded for their efforts in the form of points, earned badges, and gifted badges. Those that are familiar with the Microsoft forums will see a lot of similarities.
Much of the functionality in those forums has been built into the SharePoint Communities Sites. Additional components that are found in social networks such as “liking” a post are also included.
This set of functionality can be extremely powerful in encouraging the sharing of knowledge and contributing of content.
You can create the new site or you can activate the feature in existing site collection to use community site.
Site Settings->Site Action->Manage Site Features – Activate the “Community Site Feature”
Site Settings->Site Action->Manage Site Features – Activate the “Community Site Feature”
if you are not able to see the “Community Site template” first activate the “SharePoint server standard collection feature”.
