How Do You Use The Little Circled Lowercase I In The Top Right Corner

[RagingR6]

Ok so on youtube I've noticed a lot of people now have this little i with a circle around it that is a link. Where the hell is that and how do I use it?

 

[Viper1350]

I think you're referring to the YouTube cards:

https://support.google.com/youtube/answer/6140493?hl=en

 

[RagingR6]

Ah yes thank you!

 

[Viper1350]

Ah yes thank you!

You're very welcome