Rounds are what rows are called when you're knitting in the round. (a tube, like socks, mittens, sleeves, or sweater)
Two kinds of stitch markers; one kind goes on your needle and is used to mark the beginning of a round or where you need to increase or decrease or for stitch pattern repeats. The other kind attaches to the actual stitches and is used to mark a point that you might be measuring from later on.
Waste yarn is any kind of scrap yarn you might have left over from another project and can be used for provisional cast ons or as a stitch holder.
What do you want to know about fingerless gloves? A more specific question is answered more easily, though I have a feeling the other questions are what you've encountered in the pattern and need to know what they mean...