Wondering what weight that mystery ball of yarn is that's been in your stash for years? Or maybe the label for a yarn you just bought doesn't tell you if it's a sport or DK or worsted? How can you know what weight a yarn is without a label or a person telling you?
A knitted rib is a stitch pattern combining knits and purls to make vertical stripes of each stitch. The most common ribs are 1 x 1 and 2 x 2, but there are dozens of variations.
Adding new yarn is most often used when you need to add another skein of the same yarn to continue a project, but it's also the same technique if you need to add a different yarn or color.
Wrap & turns are used when making short rows which add shaping to your work. When working a short row, you work partway through a row or round, do a wrap & turn, then work back to the other end of the row or round without finishing the first one. Most often you do several wrap & turns in an even number on both sides of your work.