How it works
Think of the keyboard as a building with three floors and a lift. Home is the middle floor, with the top row above and the bottom row below.
A finger rides up or down, taps, and rides back to the middle. The lift goes straight up or straight down.
The golden rule: only the finger that reaches should move. The other fingers stay home and keep the place.
Words that mix the home, top and bottom rows use all three floors.