As previously mentioned, my parents purchased a "Wool Winder" for me for my birthday. My mother asked me not long after if it did what it was supposed to do, and I was reminded how many people don't know about winding yarn into balls, what a "swift" is, etc.(knitters included). So here's your tutorial:
1. Not all yarn comes in a skein like you think of coming from a craft store, the skein we're all familiar with which just unwinds from the center or the outside. Some yarn comes in a skein like these: Which will NOT unwind simply. They unwind like this:
They're just big loops of yarn, twisted up to prevent tangling.
2. To use these skeins you must wind them into a ball. "In the old days", a woman would enlist her husband or children to hold the skein on their hands and she would wind a ball by hand from this. Some people still do that, but it's not always a "woman", or "husband", or "children". I personally experimented quite a bit with chair backs and tripods to replace the husband or children, although I'm still a "woman".
3. These days, most knitters who encounter any number of these pesky un-wound skeins will acquire a "swift" which holds the yarn, and a "ball winder" which winds the ball with a turn of the crank. I considered making a movie of this for you, but found a suitable substitute on YouTube. You will find this little girl much cuter than I.
After all the yarn is transferred from the swift to the ball winder, you take it off the center piece, and it looks like this:
Ta da! Ready to knit with -- a center-pull ball. And it only took two minutes (once I found my swift) and I didn't have to enlist the help of curious onlookers or various household objects.