What is a Custom Audience?
Really solid blog post by the guys over at Social Media Ad Genius. Custom Audiences need to be a part of any and all targeted marketing campaigns on Facebook.
Facebook’s custom audience feature enables you to create an audience by using data in your own customer database, such as email addresses and/or phone numbers. You can then simply upload a list of these email addresses or phone numbers (a minimum of 100 people) and Facebook will then deliver an ad to those people, if their email & phone number information matches their Facebook account.