I know a lot of knitters are very passionate about this topic. For me, as I said above, they are all yarn overs, and I don't get too particular what "kind" of yarn over it is. I just do it. I knit to relax, and really don't need to stress over a hole in my knitting.
Here is a printable reference guide on yarn overs, including what to do when you forget to make one and what to do when you make one you don't need. There is also a video which demonstrates everything on the sheet. I hope this helps anyone who may be as confused as I was. Happy Knitting!
Yarn Over 101 Reference Guide