Within Apple Podcasts, you may see an episode labeled as a Trailer or a Bonus episode. These are different episode types that can be set in your episode details page in Buzzsprout!
A trailer episode is typically used as an introduction episode in your feed. This can be helpful to give your listeners an idea of the podcast before they commit and subscribe. These episodes are typically pretty short and straight to the point. When set as a trailer episode the episode will show at the top of your Apple listing (with the Apple Podcasts app) for any non-subscribers.
A bonus episode is different from a regular episode because it is not typically released on your usual release day. This would be for an episode that is released as a special episode for your listeners. Marking it as a Bonus episode in Buzzsprout allows you to set it apart from your full episodes while keeping your episodes in the right order!