In circular knitting, double-pointed needles are used when circular needles are difficult to manipulate. Use double-pointed needles in circular knitting with tips from a knitting teacher in this free video on knitting in the round.
So, at some point as you keep producing the number of stitches that you have, it's going to get too hard to manipulate the stitches around this circular needle. It's just going to get too tight, it's going to stretch the needle and the stitches. At that point, you want to switch to your double pointed needles, and you're going to knit with one double pointed needle off from your circular needles. So, you're still doing the same thing, you've got two needles in your hand, and you're just going to move it along, and you're going to work these stitches off the needle, keeping your markers in there, and manipulating the stitches to keep moving along. Then, I pass my marker over, and keep knitting on to that one marker, that one double point needle, and then, when I've got enough on the double pointed needle, I'm going to slide the stitches into the middle of that needle, so it's not going to go anywhere. And then I'll leave that alone. I'll take the next double point, and I'll knit on to this one. And this is the other way of knitting with circular needles, or knitting it around is on double points, so the double points help you get to those smaller spaces. Unlike the straight needles and the circular needles, they come in sizes from one to, you know, seventeen or nineteen, or whatever it takes. And it is a little cumbersome until you get them all on the needle. And, now I'll go to my third needle. Basically, you need a minimum of three needles with your stitches on it to work in the round, so I'm going to slide these last stitches onto the end of the circular needle, and my other double points are hanging in there, no stitches are falling off. That's because of the bamboo, it keeps it from being slippery. And then, when I'm done, I put aside that circular needle, and now I've got my stitches ready to be knit on the double points.