The “Magic Loop” technique is a way to knit socks or small circumferences using one circular needle. The length of the circular needle you use should be about 3-4 times the circumference of your knitting. So.. for example, if you were to make a pair of socks.. use a circular that is at least 29 inches long.
Magic Loop knitting is a handy alternative method for those who tire of losing their double pointed needles. Another alternative method that is popular for knitting small items in the round is using Knitting Socks on Two Circular Needles|two circular needles.
There are also oodles of resources and tutorials on the net for knitting Magic Loop style.
Patterns that feature Magic Loop knitting:
2 socks at once: