What is a Client Version?

In the save playlist window, you'll see a checkbox option to make the playlist a Client Version: 

A Client Version is just an internal flag you can use to signify to your team that the list was the one sent to the client and/or the final list.

It doesn't affect the behaviour or appearance of the playlist for the end user; it's just an internal flag that shows up in the playlist pane for that playlist: 

You can use the client flag in our Reports feature.