When Instagram ads was added to Facebook’s ad offering, many people assumed that the two placements would be nearly identical in terms of best practices, cost, and engagement rates. Not true.

Though Facebook and Instagram ads have coalesced well in one ad system, it’s still crucial to consider them as two very unique platforms.

They are similar, but they’re far from identical, and for brands who are used to Facebook ads—this is what you need to know before you run an Instagram ad campaign.

1. There are two types of Instagram ads

There are two types of Instagram ads: ads that will appear in the mobile feed, and story ads.

Mobile feed ads will appear in users’ Instagram feeds, much like Facebook’s regular News Feed ads. Like Facebook’s News Feed posts, they can consist of several different types of ad formats—including a single image, a video, or carousel ads that use both— and they can be saved like normal posts. Unlike the organic posts surrounding them, these ads will let you add clickable CTAs that take users to the destination of your choice.

We don’t yet have a Facebook equivalent for story ads. They’re part of Instagram’s Snapchat-like feature, and play in between organic content from users your viewer follows. They’ll take up a users’ entire screen (requiring content with a 9:16 image ratio), but they’re shorter than regular videos, and once they’re gone users can’t scroll back.

They’re good for building brand awareness and sending traffic to your site.

2. Both types of ads are mobile-only

While you can access Instagram from your desktop, ads are only shown to mobile users. This makes sense, since Instagram was designed as a mobile app.

Advertising must plan their Instagram campaigns accordingly. A “buy now” ad that takes users through a complicated checkout process might not perform…