Neovim has several modes, each with different key behavior. Master the mode system to edit efficiently.
Normal mode — default, for commands. Cursor is a block. Enter from any mode by pressing Esc. Commands move, delete, copy, change. Most time is spent here.
Insert mode — for typing text. Enter with i (before cursor), a (after cursor), I (start of line), A (end of line), o (new line below), O (new line above). Exit with Esc.
Visual mode — for selecting text. Enter with v (character), V (line), Ctrl+V (block). Move cursor to expand selection. Apply commands to selection. Exit with Esc.
Command-line mode — for ex commands. Enter with : (command), / (search forward), ? (search backward). Type command, press Enter to execute. Exit with Esc.
Switching modes:
Normal → Insert: i, a, o, O, I, A Insert → Normal: Esc Normal → Visual: v, V, Ctrl+V Visual → Normal: Esc Normal → Command: :, /, ?
Replace mode — like insert, but overwrites characters. Enter with R, exit with Esc. Rarely used; normal + commands are usually better.
The mode indicator appears in status bar (shows “– INSERT –” in insert mode). Understanding modes is fundamental—commands work differently in each mode, so always know which mode you're in.