About Knitting Needles
Knitting needles are used in pairs to produce a flat knitted fabric and come in a range of sizes based on the diameter. They are usually made from aluminum or plastic, but are also available in wood and bamboo.
There are 3 types of needles: straight, circular, and double point.
Straight needles are what most people picture when they think of knitting needles. Straight needles come in pairs, and each needle is pointed on one end and has a topper on the other end to prevent stitches from sliding off. Straight needles come in two standard lengths -- 10" and 14".
Circular needles consist of short needles that are attached to each end of a flexible cable. They can be used to knit flat projects as well as tubular projects (such as hats). Some people prefer to use circular needles for all of their knitting.
Double-pointed needles, as their name implies, are short needles with points on each end, and are usually sold in sets of four or five. Double-pointed needles are used to knit tubular fabrics such as socks and hats.
If you are having difficulty obtaining gauge or working smoothly with a particular type of yarn, consider changing the type of needles you are using. Try several different needle styles to find what you're most often comfortable with.