What does “Allow Selecting” option do?

Hello, I am still learning how to use your plugin, and expect to use it in a new project I am working on. Please help me understand the following.

On the EDIT TABLE screen there is an option to “Allow Selection”. I assume that after checking the box there are other steps to implement this, but I cannot figure out what those are, or what “Allow Selection” actually accomplishes.

I have read all of the supporting documentation I can find. Can you clarify please?

Thanks for the excellent plugin.