Notebook User Interface
Knowing the interface cold makes notebook work dramatically faster: cell modes, shortcuts for running and editing, the kernel menu, and the toolbar. Most daily work happens without touching the mouse.
Cell Modes
| Mode | How to enter | What you can do |
|---|---|---|
| Command | Esc | move, copy, delete cells; change type |
| Edit | Enter | edit cell text |
The border color tells you the mode: blue is command, green is edit. Press Esc or Enter to switch.
Command-Mode Shortcuts
- A / B - insert a new cell above / below.
- D then D (twice) - delete the selected cell (with confirmation).
- M / R / Y - change cell type to Markdown / Raw / Code.
- Up / Down arrows - move the selection; shift-up/down to move the cell itself.
- I - insert a cell and enter edit mode.
- L - toggle line numbers; O - toggle output; 0 - clear output.
Edit-Mode Shortcuts
- Shift+Enter - run the cell and select the next one.
- Ctrl+Enter - run the cell, keep the selection.
- Alt+Enter - run the cell and insert a new one below.
- Ctrl+; - insert a comment (or the language's comment token).
- Ctrl+/ - line comment; Tab - autocomplete.
Menus and Toolbar
- Kernel menu: interrupt (stop a running cell), restart, restart & run all, change kernel.
- View menu: toggle line numbers, output area, command palette.
- Cell menu: edit metadata (cell tags used by tools like nbgitpull or test runners).
- The command palette (Ctrl+Shift+C / Cmd+Shift+C) is a searchable index of every action.
The Daily Loop
# muscle memory for most notebook work:
# edit cell -> Shift+Enter -> review output -> A (new cell below) -> repeat
# cleanup: Esc -> 0 (clear outputs) -> Ctrl+SSummary
Master the two cell modes: Esc for command (A/B for cells, D D to delete, M/R/Y to change type) and Enter for edit (Shift+Enter to run). Use the Kernel menu to interrupt or restart, the command palette for anything else, and the shortcut loop edit-run-add for fast iteration.