There is also Continental and English knitting (aka American). English knitting is called throwing the yarn while Continental is considered to be picking the yarn. YouTube doesn't make a distinction though. You have to know what you're looking at when you see it.
|Continental Combination Knitting (fast on purpose. Slow below)
Continental knitters hold the yarn in the left hand while English style knitters hold the yarn in the right hand. This distinction has nothing to do with dexterity or handedness. (Knitting left handed means working stitches from the right needle onto the left needle. I don't know why anybody would do that to themselves. All patterns would have to be transposed. There is also knitting backwards, which is useful and I will cover later.)
Holding the yarn in the left hand does not require any fine motor skills in the left hand. All the complex work is done with the right hand. There is just a fast flick of the left wrist. I know that as a right handed person I only get serious pain in my right hand, never the left. Of course this could be from everything else I do right handed that has worn out my right hand and wrist. (I'm looking at you, Felco pruners.)
|English Style aka American Style
I honestly have nothing against people who knit this way. I happily watch their videos with no confusion. I think it is probably way easier to see what they are doing. (Disclaimer: The above GIF is me trying to copy the way I've seen people knit on YouTube and I have no idea if I'm even doing it right. I don't know how they actually hold the yarn to keep the correct tension. This is meant to just be a rough comparison of the techniques. Think more "What language are they speaking?" and less "What did they just say?")
What ultimately determines how much you enjoy your knitting is how much it makes your hands hurt and how does it look when you finish. While throwing or picking the yarn won't matter to the finished product, how MUCH yarn you throw or pick will. Meaning it's important to keep the same tension for purl and knit stitches. This is why I knit combination. It's always an underhand motion of the needle to pull the yarn through the stitch. Lots of blogs address what to do about something called "rowing out." This is when straight knitting looks lumpy because purl stitches put more yarn in every other row than knit stitches when it's done the "correct" way.
Combination is a more balanced way of doling out the yarn. Also in "correct" knitting the purl stitch is wrapped the opposite way of the knit. A lot of people find this difficult and sort of hate to purl. In combination you wrap the yarn the easy way all the time.
Here's a GIF with a knit stitch (on the front of the work) and a purl stitch (on the back of the work) mashed together and put on repeat. I slowed down the needle scooping the yarn to try to emphasize how it's the same motion. The knit side of the fabric is the smooth side that flips to the front. The purl side is the bumpy side that flips into shadow.
|Knit in back. Purl in front.
Most patterns are written for Western style. If it's all garter stitch then everything still works for Combination. If you never purl then the working leg is always in the front and you knit just like Western knitters. You only knit into the back leg of the stitch if you purled it from the other side. If you are knitting stockinette in the round you always knit in the front leg of the stitch.
To transpose Western patterns to Combination learn to read and feel your knitting to know which leg of the stitch to work.
Once you know that they expect the front leg to always be the working leg you can do any increase or decrease that contains a stitch purled on the last row by simply flipping the stitch on the left needle to the Western orientation before you work it. This is relevant for slip-slip-knit (SSK) and knit 2 together (k2tog) as well as for knitting through the back loop (ktbl). Purl 2 together on the purl side of stockinette, no change necessary. I'll do a post on all this later.
Note on Fisherman's Rib video link (Illustration for Eastern Style above): Fisherman's rib is one of the first things I knit because I loved how the video presenter said "knit one below." I never really figured out how she was wrapping the yarn (Eastern Style) so I kind of just did it by feel. I am sure I was getting my stitches twisted all kind of the wrong way. But by knitting in the stitch below on the next row the stitch orientation on the needle is totally irrelevant. You can wrap the yarn any which way with fisherman's rib and it comes out the same. I even knit a cowl in fisherman's rib in the round on circular needles where every other row you have to purl instead of knit, purling the wrong way without knowing it. But in that stitch pattern the whole front leg/back leg thing doesn't even matter. You work the one below the stitch you twisted on the last row. The twist untwists itself as it falls down over the stitch making the fabric extra thick. It was while doing a long scarf in fisherman's rib I got muscle memory for purling underhand. Then I had to do more research to figure out what was going on. I was happy to learn that combination knitting had a name and even a few YouTubers.