What does Attach to Side(s) mean in Create Artifact dialogue box?

Hi all,
I just signed up on these forums today. I searched several different ways to find my answer and have also searched on the web. I can't seem to find where there is something that explains the options under the Create Artifact dialogue box. I know that basically Creating an artifact is so that a screen reader won't read it. But when I right click on the object and select Create Artifact, then I get this dialogue box that says Artifact Type. Then there are 3 options (Page, Pagination, Layout). I'm not sure what the difference between Page and Layout is. Pagination I'm assuming is for page numbers and such that don't need to be read in the flow of the rest of the pdf file. But then the other section I'm not sure about what it means is Attach to Side(s). The options are Left, Top, Right, Bottom. It seems it's optional as they are check boxes. But what does that mean or what does it do if I attach an artifact to a side?