If you're new to fibre crafts, you may find the enormous choice in yarn types overwhelming. Let's try to demystify some of the more common yarn types and fibres so you know where to get started!
This guide does not encompass all types of yarns, just some of the more common ones. Also note that I'm a knitter and not a crocheter, so this guide is written from a knitting perspective.
If you're more interested in sewing rather than knitting/crochet, please check out my fabric guide.
Yarns have varying thickness: this is called yarn weight. The weight of your yarn will influence your knitting gauge, so it's important to pick the right weight for the right project. Each yarn weight requires a different needle size, too: the thinner your yarn, the thinner your needles.
Yarn weights can go by different names, but these are some of the most common ones:
Lace: lace yarn is one of the thinnest yarns out there. It's commonly used for delicate projects such as intricate summer scarves or doilies, or to knit lace trims.
Fingering: fingering yarn is a bit thicker than lace yarn, but still very thin. This yarn weight is used for light-weight projects such as baby garments, delicate socks, or thin garments.
Sport: sport yarn is twice as thick a fingering yarn and is often used for socks, accessories, shawls, and thin sweaters.
DK: DK is slightly thicker than sport yarn and is used for the same purposes.
Worsted: worsted yarn is one of the most common yarn types you'll find. It's a mid-range yarn weight that's great for a wide variety of projects, ranging from clothes to scarves, accessories, sweaters, and amigurumi.
Chunky: chunky yarn is thick and bulky, which makes it great for quick, thick projects such as blankets and rugs, or bulky scarves and sweaters.
(Image source) [ID: six yarn weights: lace, fingering, sport, DK, worsted, and chunky.]
(Image source) [ID: standard yarn weight system: categories of yarn, gauge ranges, and recommended needle and hook sizes.]
Just like fabric, yarn can be made from a variety of fibres, among which animal fibres, plant fibres, and synthetic fibres.
You'll also find blended yarns, which combine different types of fibres into one yarn, and novelty yarns, which are usually synthetic and used to create special effects such as fake fur or a metallic sheen, for example.
Let's take a look at some of the most commonly used fibres:
Animal fibres are made from the fleece/hair of certain animals. These fibres are long-lasting and will keep you warm in winter and cool in summer. When done properly and in an ethical manner, harvesting the fibres needed to make these yarns will not hurt the animal (with the exception of silk, unless you use peace silk).
Wool is prone to shrinking and felting if not washed correctly.
Sheep: the most common woollen yarn type, and therefore also the cheapest. Very soft and absorbent, great for winter. Some people find it itchy, and it can trigger allergic reactions.
Alpaca: very warm, and softer than sheep wool. Hypoallergenic, so a great choice if you're allergic to sheep's wool.
Cashmere: warm, soft, smooth, and much lighter than sheep's wool.
Mohair: light, warm, very fluffy. Has a nice sheen to it. Can be tricky to knit due to its fluffiness.
Angora: light, soft, fuzzy, and incredibly warm.
Silk: smooth, breathable, strong, soft, and shiny. Unlike the other fibres on this list, silk is not made from hair or fleece, but from the cocoons of silk worms.
Plant fibres are made from cellulose, a plant component. They're known to breath well which makes them great for knitting clothes, but often lack elasticity.
Cotton: light, absorbent, and durable, though not very elastic. Great for beginners. Can become a little rough after washing, so make sure to take proper care of it.
Linen: strong and durable, but can be a bit stiff. Very breathable. Will keep you cool in summer. Prone to wrinkling.
Bamboo: drapes well, and is very soft! If other plant fibres cause sensory issues for you, give bamboo a try.
Synthetic fibres are oil-based fibres which means they won't biodegrade and don't breathe well. However, they're cheap and durable, which makes them handy for beginner's projects.
Acrylic: doesn't breathe well, but is warm, machine-washable, and probably the cheapest available yarn option. Comes in varying qualities, ranging from horribly itchy to "I can't believe this is acrylic".
Rayon: a semi-synthetic fibre, as it's made from plant cellulose but then turned into insoluble fibres. Very soft, but needs extra care when washed.
Nylon: very strong and stretchy, which is why it's often mixed into sock yarn blends and such.
Polyester: a type of plastic fibre that's often blended in with other yarns to make them stronger and less likely to shrink.
There are many options available when you're looking for the perfect yarn for your next project. Getting acquainted with different types of yarn will ensure you pick the right material for whatever you're making.
If you've got a specific yarn in mind but want more info before you buy it, or if you've found a mystery skein that's gone out of production years ago while thrifting, get yourself a Ravelry account. You'll find reviews of pretty much any yarn brand you can imagine in their yarn section.
New to knitting? Check out my Knitting 101 guide.
Looking for cheap and preferably sustainable yarn? Check out my guide on crafting on the cheap.