What is the difference between wool spinning and worsted spinning

Update: 16-11-2020
Abst: Woolen spun, and Worsted Spun. Back semi-worsted yarn in "Ye Goode Old Dayes" all spinners would process their own fleece or have a small child, ...
Woolen spun, and Worsted Spun. Back semi-worsted yarn in "Ye Goode Old Dayes" all spinners would process their own fleece or have a small child, or hefty man do it for them; more on that later and then use one of 2 spinning types to produce 2 very different yarns. Roll forward to modern times, and the wider variety of spinning fibres we have on offer and things aren't quite so clear cut, but Woolen and Worsted are still useful things for todays spinner to wrap their head around.​It's a wordy blogpost, and heavy on video content, because nothing beats seeing these techniques carried out.We'll start off with what the yarns feel like.Woolen yarns contains lots of air, they're light, fluffy, and will often have small ends of fibre poking out of the yarn structure. They're incredibly elastic and bouncey. Jamiesons and Smith 2-ply Jumper weight is a classic commercial example of this type of yarn.
57% wool mixed yarn
Worsted yarns are smooth and dense, they tend to drape well and be much more lustrous. Many commercial yarns are spun in this way, particularly sock yarns.The 2 skeins below were spun using the 2 different techniques, you can can see how much smaller the woolen skein is, but when held under tension will stretch out to the same length as the worsted skein.Woolen spun is traditionally spun from carded rolags this was the job small children carried out. It's then spun with the twist entering the drafting zone in a long draw technique. This video of a Navajo Weaver has long been a favourite of mine. You can see her producing rolags, and then using a navajo spindle to do a form of long draw.Carding, and the rolling in to a rolag creates a spiral of wool fibres wrapping round the tube. You then spin using a long draw technique that maintains that rolled structure. The yarn isn't smoothed, it's simply stretched out like a piece of chewing gum, that traps lots of air in the yarn, and makes it very bouncey and elastic.
There are various form of long draw, some make more air filled yarns than others, but the one thing they have in common is that drafting backwards motion, allowing twist to enter the drafting zone. As a beginner it can require a bit of faith, we're generally taught to spin using a short forward draw, where letting twist past our front pinching hand can make it very hard to draft. This method requires twist to be be present however, as it's the twist in the drafting zone that controls the yarn thickness. Once you get going it's very easy to make a surprisingly consistent yarn using this method, as the yarn thickness almost becomes self controlling. Twist naturally navigates to thinner points, and those parts won't draft out further as they have enough twist to hold together. The thicker parts have less twist, and as you pull back they will become thinner, the twist travels in to them and the yarn becomes even.Historically this yarn was spun on Great Wheels. These wheels existed long before wheels with treadles, and because one hand was required to turn the wheel you needed to do a  single handed drafting technique.
They were an incredibly efficient way of producing a lot of yarn, very quickly. Long draw is still may favourite technique when I need a quick skein of yarn. Worsted Spun requires a very different fibre preparation, and spinning technique. While woolen spinning is all about trapping air, worsted does the exact opposite. Instead of carding the fibres they're combed. Hairs are aligned to be parallel, instead of being rolled up to perpendicular to the direction of the yarn. Twist isn't allowed in to the drafting zone, and a short forward draw is used this is the most common technique most modern spinners use.Combing was traditionally done on large heavy combs, and was done by men. These are actually a scaled down version of the historical combs, but having handled a pair I can tell you that they're still seriously heavy to handle. As modern spinners we can now get some much smaller and lighter combs, but combing is still a real physical workout. No need to go to the gym if you do an hours wool combing!