Yardage / Meterage
The number of meters or yards of yarn per skein or per 100 grams. Important for yarn substitution.
Explanation
Yardage (or meterage) tells you how many meters or yards of yarn you get in a skein or per 100 grams. This is the most important factor when substituting yarn in a pattern. Two yarns may weigh the same but have completely different lengths. A thin yarn has a longer yardage than a thick yarn at the same weight. When substituting yarn, you must calculate how many skeins you need based on total length, not number of grams.