Official posts are posts (news, surveys, events, lists of helpers, finding dates, etc.) that are not only visible to members of your community, but also to people who are not registered on beUnity.
This means you can create posts in there that you can share with people (via Facebook, Twitter or WhatsApp) without them having to have a beUnity account. This way, an important event can also be made known outside your community. You can also easily share this post by copying the URL link and sending it to the relevant people.
You can find out how to create an official post here.