Knowing the difference between yarn weights is important when selecting a yarn type for your project. For instance, a worsted weight, which is the most common yarn type you will find in a store, is too bulky of a yarn for dainty socks. Those socks would require delicate fingering yarn, which, in turn, would not work for a winter beanie.  The best way to look at it is that a heavy, jumbo yarn should generally be limited to arm knitting, whereas bulky, roving, and chunky yarns would best suit those cropped sweaters and cardigans you’ve been eyeing on Instagram as well as cozy scarves, rugs, and throws.  And when it comes to the finer yarns, you can expect that lace and sock (also known as fingering) weight yarns would be best for their namesake projects, while sport and DK weights are better for all-season apparel, like knit tops and dresses. Finally, worsted-weight yarns, which have a medium weight, are ideal for apparel like sweaters, beanies, mittens, and other winter-weather projects. Knowing your yarn weights will also help decipher which needles or hooks you should use. Usually, you can find that info on yarn packaging, but keep in mind that you should use smaller needles for lightweight yarns and larger ones for bulky yarns.