I learned to type before I had a computer at home. One summer when I was 9 or 10 my mother sent me to a typing class. We used word processors to learn touch typing, starting with individual keys and then transcribing passages from paper. We were tested on accuracy as well as speed. It was extremely boring, but being able to touch-type complete sentences with very few typos has been an exceptionally useful skill. Back then very few computer programs had live spell-checking.
Around 2003 I switched from QWERTY to the Dvorak keyboard layout. I honestly don’t recall why – I probably just wanted to try something new. I’d heard you could type faster with the Dvorak layout, and that you would have fewer repetitive strain injuries (RSI) from typing. Using the Dvorak layout didn’t change my typing speed much either way, but I’ve had very few issues with RSI since I switched. The switch itself was physically painful – “reprogramming” over a decade of muscle memory.
I’ve never used an actual Dvorak keyboard. I use QWERTY-labeled keyboards made by Kinesis, and change the layout in software. Not having accurately labeled keys made it tougher to learn the Dvorak layout initially – especially the various mathematical symbols used in programming.