We use APIs all the time in our every day life. We just don’t always know it. For example, each time you use an app like Facebook to send an instant message, you are using an API.
In OOH APIs are used to expose and receive information like price and availability between two automated systems. For example an API is used to deliver information about price and availability from a buyer’s request in their planning system and the media owner’s inventory management system.
You can read more about how APIs are used to power OOH trading in this blog post.