Circular Needles Vs. Double-Pointed

Hi,
I’d like to knit a hat for my mom, but the circular needle I have is too long at 24", so I can’t join the round. I have a pair of double-pointed needles, and I think I can easily knit the hat on them, but I’m wondering if this would alter the gauge somehow, or mess up the pattern? Aren’t double-pointed needles and circular ones essentially the same, in that I can use them to achieve the same results? Sorry, but I’m a bit confused! Not to mention broke, which is why I’m hesitant to go out and buy another pair of circulars!

Yes, you can work with the dpns. They were around before circular needles. For a hat, you should be fine as long as the stitches fit.
There are ways to work small diameters with circulars, such as magic loop and knitting with two circs.
http://www.knittinghelp.com/videos/advanced-techniques

You can use the dpns just fine, but you may get a slightly different gauge on them. I do a lot of the time. I tighten up because of the extra needles, but not everyone does that, and you could adjust the pattern or just consciously knit looser if you find your gauge changes.

Thank you both!

You can actually knit a hat on 24" needles. I answered in your other thread - http://www.knittinghelp.com/forum/showpost.php?p=1195547&postcount=3