Wrap, or YO, or what?

Hello again:

I am working with those Charisma baby books again and the instructions say “wrap”. It is in the beginning of a sleeve and it looks as if they are beginning the expansion process, but I am not sure what “wrap” means. Is that a yarn forward, yarn back, loop over ?

Any insights about sleeves will be welcome!

Wrap is usually used in conjunction with short rows. If you scroll down on this page you’ll see info about short rows with a wrap. The wrap is used to help prevent a hole.

Thank you!