I have been touch typing for a long time. Occasionaly, I suffer from wrist pain. I am not a programmer. And I do not type very fast, (although I type faster than anyone I meet in real life).
I like tinker with computer, but I am a doctor. Here are some thoughts on typing as a whole and how to avoid injury.
According to my observation, there are a few different types of typers.
I call them finger typers because they always use one or two fingers to do most of the typing. They cannot type without looking at the keyboard. They cannot remember where every keys are at. Finger typers needs to move their eyes back and forth between the monitor and the keyboard. On a setup where they cannot do that with moving eyeballs, they would have to move their head, resulting in neck pain or minor disalignment in the neck.
Using only a couple of fingers to do all the jobs requires you to move your hands, wrists or even arms. This can lead to more problems in the upper limbs.
However, since finger typers type fairly slow, and most of them are not using computer frequently, pain are rarely observed in this type of typer.
Eye typers maintain the perfect position to put their hands on the keyboard, e.g. putting both index fingers on F and J respectively. They also insist on using the correct finger to type the correct character. These group of people is novice of the touch typers. The only difference is that eye typers have not remember the key position yet and rely on their eye to confirm. Not every eye typer can evolve into touch typer. What they lack is confidence but not memory.
The biggest characteristic of them is the constant peeking of keycap, since maintaining the default position blocks their eye sight, and they do not want to give up their hand position when using their eyeballs.
Freestyle typers utilize both hands, all the fingers, but in a unique way, (or weird way). They type fairly fast without mapping the correct finger-to-key relationship. They learn their technique by being forced to type at work or in school. What they want is to get the work done. Typing is just a way to achieve their goal. They sometimes rely on eyeballs for some uncommon characters, especially those weird symbols on the right side.
I regards freestyle typing as a bad habit because it is not an efficient way to type. If you want to type faster as a freestyle typer, you will hit a hard brick wall as accelerating. Bad habit is very hard to correct.
Touch typers do not look at the keyboard, they can type with their head no moving and eyes looking straight at the monitor. They barely move their hands. Fingers are the only moving parts of their body. They maintain the perfect finger-to-key relationship. They can type really fast.
Touch typing is regarded as the ultimate form of typing.
It is great for anyone who uses computer for an extensive period of time to learn touch typing.
There are a lot of ways to become a touch typer. There are a tons of websites providing games for practising touch typing. (I have never use any of them).
I recommend two ways to become a touch typer.
Use a keyboard without printing on keycaps. It forces you to remember the key positions.
Turn off the light. If you cannot see, touch and try.
These are the fastest way to achieve touch typing.
If you are at the stage of touch typing, and wondering why you still have broken wrists, that is because you are typing it wrong.
The key of touch typing is touch. But some touch typers hit their keyboard very hard. That is punch typing. Listen to the sound you make when typing. Good typing should make very little sound, because you should be typing with the minimal force.
That's why I don't understand why people use noisy mechanical keyboard. If your typing sounds like clapping, good luck to your hands.
This is a mistake for a portion of touch typers. Space is a very common key of the keyboard. It is large, and it usually requires more force to press down. Touch typers should alternate between thumbs to type the spacebar. My recommendation is to use the other hand of the last key press, it is faster.
Companies making low profile keyboard should go to hell. The only acceptable appearance is a laptop keyboard. If you are using an Apple Magic Keyboard and wondering why your hands suck, that's where magic happens.
Low profile keyboard does not have a cusion effect to the finger, which is not good to the finger joints, and often leading to the use of excessive force.
The ideal resting position of typing is maintaining a straight line between your forearm and hand. You should not bend your wrist when typing. The solution to this is to use a wrist rest, preferably a wood brick instead of a cusion to provide enough support.
A lot of keyboards come with a little leg to tilt it up. Do not use them.
You can type very fast with touch typing. But typing too fast for an extensive period of time causes fatique and loss of power control.
As the time goes, you may be typing harder than normal because of fatique. You need rest in between each burst of speed. Touch typers do not need to maintain an inhuman speed. The normal speed of touch typers is already much faster than normal people.
Here are some ways from the Internet claiming they can improve typing speed and relieve pressure.
The normal layout we see on the market is the QWERTY layout, which is invented for the typewriter to avoid jamming of ancient mechanical parts.
QWERTY was not invented to increase typing speed. And here comes DVORAK layout, which is to provide a more relax and faster way to type English.
I do not use DVORAK layout, because only English can benifits from its weird layout. I type multiple languages with keyboard, using DVORAK makes other input methods nearly impossible to use. Of course I can switch between QWERTY and DVORAK for different input methods. But I am not a writer, and I program for fun. The little increase in speed does not mean much to me.
Really? This is usable in a very limited use cases.
There are a lot of shapes of keyboards, spit, vertical, etc. In my opinion, these kind of weird keyboards are for people who have already been injuried, maybe from typing too much or typing wrongly.
However, a good keyboard is important. I have been using HHKB for years. The touching and the slightly modified layout is second to none. But I don't recommend people to buy HHKB. First, it is expensive. Second, you cannot go back using a normal keyboard afterwards.
If you maintain a good typing habit, a decent keyboard with enough travel and rebounce is more than enough. Some recommend using a mechanical keyboard. I personally prefer red or brown switches. Black is too heavy. And those switches with fancy stupid clicking sound should be thrown directly into rubbish bin.