Replace Mode

R โ€” overwrite as you type. r{c} โ€” overwrite one character.

Keys: R, r

R enters Replace mode: each typed key overwrites instead of inserting. r{c} overwrites a single character without entering Replace mode.

Insert mode pushes characters around: typing in the middle of a word grows the word. Replace mode is different โ€” each typed character overwrites the one under the cursor, then advances. Typing 5 characters in Replace mode replaces 5 existing characters.

Replace one char with x (stays in Normal)
KeyNote
r
x
Enter Replace mode (continuous overwrite)
KeyNote
R
r โ€” replace one character
R โ€” Replace mode

See also: Replace a Character, The Modes