Mini and Micro Skeins
I wind my handspun yarn into skeins (you might also call them hanks). Its a convenient way of getting yarn to you untangled and allows me to give you an accurate estimate of the length (count the number of loops and multiple by the length of the skein).
A Skein will be anything 30g or heavier
A Mini Skein is generally around the 20g mark so I use that description for skeins from 15g to 30g
A Micro Skein is under 15g. When the length of yarn gets down to sample territory rather than a usable length you might see Nano Skeins (bear in mind 8g of laceweight is going to go a lot further than 8g of chunky art yarn)
You'll notice that the weights of the skeins vary a bit, that's because I'm a knitter too and that makes me adverse to joins in yarn. Let me explain that a bit more clearly - when I spin say 100g of fibre on to two bobbins its very unlikely I'll get precisely 50g on to each one. I could split it evenly when I wind the skeins but that would mean taking a bit off one length and adding it to the other - you get two equal weight skeins but would find a knot in one of them!
To avoid the dreaded knots I don't even out the skeins. To make things a bit easier I group the skeins by size but always give you an approximate weight and length measurement. That doesn't necessarily mean the heavier skeins are better value, the length (yardage) is the important measurement!