An ad concept is an overarching “Big Idea” that captures audience interest, influences their emotional response and inspires them to take action. It's essentially the main message of the ad.
A hook is the first few seconds of the ad. It's also called the "scroll-stopper". We deliver each ad with 3 different hooks, so you can A/B test different ways of capturing your audience's attention while still conveying the same overall message.
This will allow you to test multiple ad concepts, and drill down to further iterate on optimize your ad creative for performance.