About the triple keyboard

I use a three-dimensional keyboard. I think the three-dimensional keyboard is the most effective keyboard for Korean input. Take a look at the advantages and disadvantages of three types, comparison of two types and keyboards, types of three types, Windows/MacOS/Linux input methods, and precautions for use. In 2001, I learned and started using the three-stroke final, and around 2010, I changed it to a three-stroke 390 keyboard and so far...