The Strongest Key in Vim Is a Dot

When the same fix is left in two more places, a Vim user just alternates n and ., two keystrokes per place. Could you say what that . actually does?

All . does is repeat the last change. That one small thing sits at the center of how Vim users edit: one key to move on, one key to do it again. The pattern has a name, and Practical Vim, the standard book on the editor, calls it the Dot Formula. People who know Vim are already thinking about it on the first change: is this shaped so . can repeat it? The moment you see the same fix in three places, the first one decides the rest.

The plainest mark on the keyboard turned into the key that gets pressed the most.