Usually, pattern calls for 4 dps. OK your pattern is different!
You have stitches on TWO dps so with the 3rd needle you
start knitting. When you knit, you have stitches on a
needle and you have empty needle to knit with!
Hope this helps.

Just curious, what kind of pattern is this? DP's are usually used to knit in the round, so what would you be doing with stitches on 2 needles?

I wonder if you are supposed to have the stitches on 3 DP's and the extra one is a "given" so to speak.

Susan

I can't see using just 2 needles and knitting with the third in rounds. Unless you are knitting back and forth and then the dangling needle would be awkward.

The reason you use 3 needles and knit with the fourth is to make a triangle so the stitches aren't pulled out of shape when going round and round.

You didn't say what you were knitting, but knitting with 4 needles is used to make something that is seamless and tubular like socks or mitts or toques.

You cast on and divide the stitches on 3 needles, join into a circle and knit the first needle with the 4th. Then you knit the second needle with your now free first needle and so on. You keep going round and round. To make stockingette stitch you just knit. The patterns are written in rounds instead of rows. One round is from the first stitch you started with around to the last stitch on the third needle

I got the hang of it (thanks jjknitter)and finished the project.
The pattern was for a 4" ghost and it really did call for 3 needles, stitches divided onto 2 needles.

Now I have a question about binding off. When I finished with binding off, there is a space between the beginning and when I ended, in other words is not joined (so I just sew a couple of stitches to close it?). Is this correct or did I do something wrong.