- Standard sizes represent regular display ad slots.
- Video sizes represent video players on a page that can show VAST (Video Ad Serving Template) ad responses.
Components of a video ad unit
A video ad unit is an ad unit that contains at least one video size.
- Required: One master video size (such as 400x300v). The master video size represents the video player size on the page. In DFP, the letter "v" appears automatically at the end of any video size, indicating that it's a video size and that it's capable of playing back videos sent in the VAST format.
- Optional: One or more companion ad sizes to run alongside the master video size.
- Optional: Other non-video sizes, such as a banner at the top of the page.
The diagram below shows a sample webpage with a video player.
The black rectangle is a leaderboard ad slot. The red rectangle with the play button represents a video player that plays back the master video ad, and the companion ad slot appears to its right.
The ad unit representing this page would contain the following sizes:
- 400x300v: master video ad slot.
- 300x250: companion ad slot (this slot may also display regular web ads not linked to the master ad).
- 728x90: web ad slot, not linked to the master video ad.