ELI5: Explain Like I'm 5

Opportunity to see

Opportunity to see (OTS) means the chance for someone to see an advertisement. Think of it like your teacher giving you a sticker, but she can only give you one if you look at her when she hands it out. If you're not paying attention or you're looking the other way, you won't get the sticker.

The same thing happens with ads. If you're watching TV and an ad comes on but you're not in the room, you missed the opportunity to see it. If you're scrolling through your phone and an ad pops up, but you quickly swipe it away, you didn't have the opportunity to see it.

Marketers use OTS to measure how many people actually had the chance to see their ad. They want their ads to be seen by as many people as possible so they can sell more products or services.

So, when an advertiser says they had a certain number of OTS, it means that many people had the chance to see their ad.