Text insertion and deletion are the core of editing in Neovim. Most operations combine a verb (operator) with a subject (motion or text object).

i — insert before cursor, a — insert after cursor. I — insert at line start (first non-blank), A — insert at line end.

o — create new line below and insert, O — new line above and insert.

All insert modes exit with Esc. Ctrl+C also exits but is slightly different (doesn't set . for repeat).

i text <Esc>     " insert "text" before cursor
A ; <Esc>        " append semicolon at line end
o print("x") <Esc>  " new line, insert code

x — delete char at cursor, X — delete char before cursor. Delete is quick removal without affecting position much.

dd — delete entire line, d3d or 3dd — delete 3 lines. D — delete from cursor to end of line.

dw — delete word, db — delete to previous word boundary. d$ — delete to end of line, d^ — delete to first non-blank.

c — change (delete and insert). cw — change word, cc — change line, c$ — change to end of line. After change, cursor enters insert mode automatically.

x              " delete char at cursor
dd             " delete line
dw             " delete word
c2w hello      " delete next 2 words, type "hello"
cw new_name <Esc>  " replace word at cursor

r — replace one character. rX replaces char at cursor with X. R enters replace mode (like insert but overwrites).

~ — toggle case of char at cursor (upper ↔ lower), g~w — toggle case of word, guw — lowercase word, gUw — uppercase word.

J — join next line to current (with space). gJ — join without adding space.

u — undo last change, U — undo all changes on current line (within one edit session). Ctrl+R — redo.

. — repeat last command. Extremely powerful: edit once, repeat with . on other lines.

J             " join lines
u             " undo
.             " repeat last edit
J . .         " join 3 lines quickly

>> — indent line right (by shiftwidth), << — indent left. >ip — indent paragraph. < and > work with motions.

For multiple lines, select in visual mode then press > or <.