Editing

The vim grammar, the mode system, and the : line — the vocabulary everything else composes from.

Topic	What it covers
Modal editing	Modal editing: Normal / Insert / Visual / Select / Command / Search / Replace, the vim grammar (operators + motions + text objects + counts), and registers / marks / macros.
Yank ring	yank-ring: every yank and delete kept in a bounded, recency-ordered history. `<C-r>{reg}` inserts a register, `<C-r><C-r>` picks from the ring, and the pick lands wherever you opened it from.
Cancelling a running operation	Cancelling a running operation with : what it stops (project search, LSP commands you asked for), what it deliberately leaves alone (automatic requests, background work), and why and are not the cancel key.
Modes	Major + minor modes: what they are, how : toggles work, major-mode swaps, auto-activation hooks, the option-resolution model.
The command line
Ex-commands	The : line: built-in commands, arg schemas, tab completion, ranges, aliases, :g / :v / :s with live preview.
Surround	vim-surround: ds, cs, ys operators — delete, change, and add surrounding pairs of brackets, quotes, and tags.
Formatting, reflow and wrapping