Finishing Sweater

I’m making a sweater for the first time and I want to just clarify a few things for the sweater, so that it turns out perfectly.

The pattern states that I have to use an edge-to-edge stitch for the ribs and a back stitch for everything else. I know how to do the back stitch, but I’m not sure what the edge-to-edge is.

Second question is in relation to the sleeves. Here’s what the pattern says:
“Sleeves
Set-in sleeves: Set in sleeve easing sleeve head into arm hole using back stitch,
Square set-in sleeve: Set in sleeve head into armhole, the straight sides at top of sleeve to form a neat right-angle to cast off sts at armhole on back and front using back stitch.
Shallow set-in sleeves: Join cast-off sts at beg of armhole shaping to cast –off sts at start of sleeve-head shaping. Sew sleeve-head into armhole, easing in shapings.”

What does it mean to “set in” the sleeves? What is the difference between a square and shallow set in?

Please post a link to the pattern if you have it and the pattern name. It makes answering questions easier since there are thousands of patterns.

Yes, a pattern link is very helpful.
Maybe this pattern?
http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=6&ved=0CC0QFjAF&url=http%3A%2F%2Fwww.knitrowan.com%2Ffiles%2Fpatterns%2FLuigi.pdf&ei=O6HQVKqvA8GgNsSlgWg&usg=AFQjCNERY265Emdqm3LXKHmo9OxTfu62Mg&bvm=bv.85076809,d.eXY
Edge to edge probably means to use something like the mattress stitch to join the ribbing at the fronts and back. You can use a mattress stitch here for a neat edge.


A set in sleeve is the usual way sleeves are attached to the fronts and back in sewing http://www.craftsy.com/blog/2014/02/sewing-in-set-in-sleeves/

The pattern gives you different ways to do the set in sleeve starting at the bottom of the circle or at the top. I usually start at the beginning of the cast off on the sleeves and body and then ease the sleeve into the opening (shallow set in) if I use this kind of sleeve seam. You can pin the sleeve in place first to see which method you like.
I find that in knitting it’s easier to leave the side seam open, join the sleeve and then stitch the long seam of sleeve and side as one.

Fusion
http://a.allaboutyou.com/pattern/58868.pdf

Thanks. Same finishing instructions so reply above applies