Some common yarn abbreviations and acronyms you may encounter in a yarn shop:
dpn: double pointed needles. Those packs of 4 or 5 pointy things that you can use to knit in the round.
fingering, sport, double knitting (dk), worsted, aran, bulky, super bulky: These are all weights of yarn. A common description is that each term refers to the thickness of the yarn, however, a more accurate explanation is that each of these refers to the density the yarn is intended to be knit at. This is often expressed as "stitches per inch" or stitches per 10cm / 4", which is called the gauge. The terms listed above are in order of finest knitting (like you'd use for socks) to bulkiest (like a thick, chunky scarf).
wpi: This is another way of measuring yarn thickness. It is a little different than gauge, since instead of looking at how dense the yarn will knit it looks at the actual thickness of the yarn, measured by wrapping it around a cylinder and measuring how many wraps there are to a measured inch. The higher the number, the finer the yarn!
top down / bottom up / toe up: This refers to the direction that a pattern is intended to be knit in. A top down sweater, for example, starts at the neckband and progresses down to the bottom hem, while a toe-up pair of socks starts at the toes and works up to the cuff.
in the round / knit flat: This refers to whether a pattern is knit in a tube (on circular needles or dpns), or as a flat piece, where you turn the work back and forth (like a scarf). You can knit flat on circular needles, but it is almost impossible to knit in the round on straight needles!
merino: This is a very popular breed of sheep that produces a fibre with a relatively low micron count (the width of a single fibre), which results in a very soft, bouncy yarn. Merino is loved for its softness, and it is very suitable to next-to-skin wear. Because it still comes from a sheep, however, it is still wool: those with allergies and sensitivities may have less issues with this fibre, but should still be careful.
blue-faced Leicester (BFL): This is a breed of sheep that produces a luxuriously soft, lustrous wool with a long staple length (staple length is the average length of the fibre). It has excellent drape, a slight resistance to felting, and is utterly delightful to work with and wear.
superwash: This means that the yarn has been treated so that it is safe to be machine washed. Most wool will felt if exposed to heat, water, and agitation, so putting that cherished handknit sweater in the washing machine is a terrifying prospect. Most superwash yarns should still be washed on a gentle, cool wash, and with a wool-safe detergent like Soak, and never put in a hot dryer. Non-superwash wools can still be washed, just by hand and with care.
needle sizes: This one is often a bit confusing, as in Canada we use both the metric measurement (which is the literal diameter of the needle) and the slightly less intuitive American measurement. Generally, if you see the letters "US" beside a number, then the sizing you're using is American, and if there's "mm", then it's the metric. If you're confused or uncertain, don't hesitate to ask us to help you!
needle length: This is usually used when talking about circular needles, but can apply to double pointed needles and even straight needles. Generally, the size of your project will determine the length you need: no matter how stubborn you are, it's difficult to knit a 48" blanket on a 9" needle! The number of stitches you cast on matters a lot less -- for example, with a fine yarn, you can fit over 150 stitches on a 40cm needle, while if you were using a super bulky yarn, you might struggle to fit 60 on. Again, if you're not sure or your pattern doesn't tell you, ask us and we'll offer suggestions!
stable: This acronym is for those of us who are true addicts, and refers to stash acquired beyond life expectancy. Given how happy yarn makes most crafters, however, it is a popular theory that you are extending your life (or possibly your enjoyment of it) with your stash!