Similar to Carousel Ads, explained above, Slideshow Ads segment your ad into individual images that users view one after another. The difference between these two ad formats is that Slideshow Ads only play images (not videos), and the ad compiles these images into a slideshow that plays automatically in the form of a video. According to Facebook, Carousel Ads are ideal for: Facebook Ads Website Conversions Campaign Tutorial 2017 - Facebook Conversions Ads Tutorial
Video Ads have a GIF or video as the centerpiece of the advertisement, and can be used to demonstrate a product or event. Video Ads help you form deeper connections with your audience by aligning your brand with a type of content online users are quickly consuming more of (nearly 80% of all data consumed on mobile devices will be in video form by 2021, according to a Facebook study). You're Optimizing Your Facebook Ads WRONG! - What to Optimize For?
Facebook will do whatever it can to protect itself from losing its users. Which represent Nearly $10B a quarter in advertising revenue. Sure the advertisers are paying that bill but without users to click the ad, Facebook would not have the revenue. And Facebook is much more interested in protecting the user experience than it is in your ad dollars.
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