This lesson covers the main YouTube ad formats: Skippable In-Stream ads (play before/during videos, viewers can skip after 5 seconds, only pay if watched past a certain point), Non-Skippable ads (shorter, must be watched in full), and Video Discovery ads (appear in search results and suggested videos, similar to a sponsored recommendation). Understanding each format’s strengths helps choose the right one based on whether the goal is brand awareness, consideration, or driving specific actions.