Connections: You can target or exclude people who have an existing connection to your Facebook Page, your app, or an event you managed. For example, if you want to reach a new audience, your would select “Exclude people who like your Page.” If you want to promote an offer or new product to existing fans, select “People who like your Page” to reach people who already know your brand. You can also choose to target friends of people who have previously interacted with your brand. Fix Can't Turn off Limit Ad tracking iOS 12| How to Fix limit ad tracking greyed out on iPhone
Here's an example of a boosted post from Bustle, who promoted one of its articles on Facebook. Paying to "boost" a post you already posted organically to your Facebook Business Page can greatly benefit content that has mass appeal -- versus a post that targets a specific segment of your audience. Bustle's choice of boosted post here falls into that first category. Facebook Dashboard in Excel
Although ads in the News Feed are likely to get higher engagement metrics due to its native advertising features, right column ads shouldn't be forgotten. We often see less expensive clicks and conversions when using these ads. In order for a right column ad to be successful, it needs to be relevant, have a value proposition, a good visual, and have a call-to-action.
You also have the option to select a Custom Audience -- this allows you to target people on Facebook who are in your company's contact database, visited a page on your website that has a tracking pixel, or use your app or game. To learn more about how to set up a Custom Audience on Facebook, check out these instructions. (And for more on the specifics of these criteria, visit this Facebook targeting resource.) How to prepare and market using Facebook Ads