Command Palette & Help
Two keyboard-driven tools make everything in the notebook reachable without hunting through menus: the command palette (⌘K) for actions, and the help dock (⌘⇧K) for documentation.
Command palette — ⌘K
Press ⌘K (or click the ⌘K hint in the top bar) to open a fuzzy-searchable list of every action, each with its keyboard shortcut. Type to filter, ↑/↓ to move, ↵ to run.

It's not just commands — entries are tagged so the palette doubles as an insert menu and a navigator:
Cell actions — add / move / delete / convert / split / merge, run stale, show a cell's dependency chain.
Panels — Packages, Worker log, Timeline.
Export — HTML, publication PDF, print, or self-contained
.jl(see Export).@bindsnippets — insert any widget (Slider,Toggle,Select, …) as a ready-to-edit snippet.Recipes — drop in a starter chart or table cell.
Jump to cell — every cell id is listed; pick one to scroll to and select it.
VS Code / project — open the notebook or its project in your editor; open Settings; jump back to the notebook index.
Single-letter and ⇧-shortcuts are command-mode (a cell is selected and you're not editing it); ⌘-shortcuts work globally, including from inside the editor.
Help & docs search — ⌘⇧K
Press ⌘⇧K to open the help dock. With the cursor on a symbol it opens that symbol's documentation directly; otherwise it's a search box over the notebook's package docs (a hybrid semantic + full-text query — press ↵ to run it).

The dock is built for drilling in, not just one lookup:
Clickable references — type names in a signature (
Vector,Float64, …) and inline $code$ names in the docstring become links; click to open that symbol's help.Exports grid — looking up a module lists its exports as chips, colour-coded by kind; click to dive into any of them.
Related rail — neighbouring/related items are offered alongside the doc.
Back / forward — ‹ › walk your lookup history; esc dismisses the dock.
Insert — ↵ drops the bare name at the selected cell's cursor (or copies the qualified name if no cell is focused).
Because it reads the notebook's environment, the help reflects exactly the package versions loaded in this notebook — including packages you added through the Packages panel.