Yes there are two differences between straight of grain binding and bias binding. The bias cut has stretch, straight of grain does not. Bias cut is used when you are binding irregular cuts, curves etc. Straight of grain is used on straight edges. There is a method to cut "Continuous" bias binding, so that you don't have to join them end to end. This works really slick, and is a real time saver ! I'm sure you have noticed that when you make half squares, and some are on the bias, that these squares stretch out of shape, compared to the straight of grain squares, which don't have any give at all. To rip out seams that are on the bias, rip every 4 or 5 stitches on one side, and then on the other side, just pull the thread, and it won't pull the fabric off of grain. Double fold binding, sewn on in a certain way, with the flip, flop and fold method, automatically comes with the mitered corners, and is a no brainer. Hope this has been helpful. If you have any questions, just call, and I'll fill you in. Greetings from Auntie B, from thawing and almost spring like Saskatchewan. P.S. I have daylillies up 3" on the south side of the house, WTH, that has to be a new record for the middle of March !!!!!!!!!!!!