Keyboard

Caveats

Most if not all pages are just rough notes, and these pages as a whole are far from complete. More notes will be added in time, eventually, maybe.

If, from reading these notes, you conclude that I am off my rocker, you won’t be the first, and you may even be right.

No doubt there are a dozen and one reasons why none of this would ever work, but perhaps somewhere deep down there is a tiny fragment that could be used for something.

Shortcuts and modifier keys

Shortcuts and modifier keys

Keyboard shortcut practice varies by operating system.

Windows shortcuts and modifiers

The general arrangement under Windows is as follows:

Control
Ctrl: The modifier key for standard keyboard shortcuts. As Ctrl+F4, closes the active MDI child window (in MDI applications) or the current browser tab, and the active window in (for example) JujuEdit and LibreOffice. No behavior if pressed as a dedicated key. Ctrl+Insert is the old and largely forgotten (but still available) shortcut for Copy; the Mac’s Cmd+C has generally replaced it in the form of Ctrl+C. When dragging a file, copies instead of move; with Alt, creates a shortcut instead of move or copy. When clicking a file in File Explorer, holding Control selects disjoint files. Control plus the arrow keys moves the selection cursor without selecting a file.
Alt: As a dedicated key, activates the window’s menu bar (same as F10). As a modifier key, invokes menus and window controls via underlined mnemonics (often invisible by default). For ribbon interfaces, activates the ribbon and narrows down the target item as a sequence of keystrokes. Also used as Alt+F4 to close the active window, which for MDI software is the entire application. Inkscape for example uses Ctrl+Alt+Shift+S
Windows: As a dedicated key, opens the Start menu; as a modifier key, invokes system-specific shortcuts (versus application-specific shortcuts). Software such as Autohotkey is entitled to add or replace Windows key bindings but applications do not use this key normally for shortcuts.
Shift: Shift increases the number of available shortcuts by allowing two shortcuts to share the same letter. For example, Ctrl+N in File Explorer opens a new window at the current location, while Ctrl+Shift+N creates a new folder in the current location. Ctrl+Shift+S can be used for Save As. Shift+Insert is the old (and still implemented) shortcut for paste, largely supplanted in consciousness by Ctrl+V. When clicking a file in File Explorer, holding Shift selects a range of files.
Function keys: A portion of the function keys from F1–F12 are bound to various tasks according to context. F1 = help. F2 = rename. F3 = find/find again. F5 = refresh. F6 = navigate between window panels. F10 = activate menu bar. Shift+F10 = show context menu. F4 is only used with Control or Alt.

For those of the MDI era, Ctrl+F4 and Alt+F4 can be very confusing, as Alt+F4 quits the entire MDI application and is worrisome when faced with non-MDI software where you only want to close a single window.

Applications and the system have separate “shortcut domains”: Windows+E (open File Explorer window) and Ctrl+E (application defined) are totally unrelated. However, Windows also suffers from a more untidy arrangement.

Mac shortcuts

Command
Cmd: The modifier key for all keyboard shortcuts. Not valid as a dedicated key. Also used for various confusingly unrelated tasks, such as selecting disjoint files (as Control in Windows) and moving a window without raising it by Ctrl+dragging the title bar (as right-drag in RISC OS).
Option
Opt
Alt: The “complement” key, e.g. Cmd+S = Save, Cmd+Opt+S = Save As. Used for input of characters beyond the range of the keyboard, either as a straight modifier (e.g. Opt+8 = •, Opt+Shift+8 = °) or for composition sequences (e.g. Opt+E, A = á)
Shift: For keyboard shortcuts, preferred for unrelated commands, e.g. Cmd+S = Save, Cmd+Shift+S = Sort Text, mnemonically as though Cmd+s is Save, Cmd+S is sort.
Control
Ctrl: Confusingly, this key served little purpose on the Mac. Absent on the original Macintosh keyboards (M0110 and M0110A), its later addition may have been for PC and terminal compatibility. Largely an irrelevance, it has since found favour in the Terminal application where it serves the same functions as in a Linux or UNIX console. For exceptional cases it was also used in modifier keys where too many items needed the same letter.
Function keys: This role has changed over time; to be documented.

Shortcut consistency

With only 26 letters in the basic Latin alphabet, care has to be taken in choosing standard shortcut letters. Having dedicated application and system shortcut modifiers (as with Windows) eases this burden considerably compared the Mac where the OS occupies shortcuts that applications cannot use (chiefly Cmd+H for hide current application).

The Mac introduced a Control key in the 1980s but assigned no purpose to it. Following the transition from a fully proprietary OS to semi-UNIX system, the Mac now has the Control key completely free for use in Terminal, keeping UNIX interaction segregated from the Mac system where the Command key is the modifier.

There are not quite enough modifier keys to suit a modern system, and so few available characters to use in shortcuts that many programs (especially graphics applications such as IrfanView, Inkscape and Adobe Photoshop) use simple keystrokes without modifier keys for simplicity and to gain more keys.

To be resolved: