What is SpaceFN and why you should give it a try
The SpaceFN concept - setting up your space key as a layer switch when held - is probably one of the most useful tweaks in the keyboard hobby. Let me explain how it works. My SpaceFN article on kbd.news made some rounds recently - quite surprisingly given the age of this concept. This piece you're reading is a condensed version of the full post. If you're left with unanswered questions, you'll most likely find the info you're looking for in the original write-up. On my imaginary top list of the most useful keyboard features, tweaks and hacks, SpaceFN would deserve a podium finish for sure. But what makes it so special? In short: SpaceFN is easy to implement, easy to learn, costs nothing, can be used with any keyboard, and can improve your productivity instantly. I will list its benefits below, but can state right at this point that the SpaceFN concept, setting up your space key as a layer switch when held, is clearly one of the most useful tweaks in the keyboard hobby....
Apr 30, 2024
http://en.wikipedia.org/wiki/Caps_lock The Caps Lock key is a modified version of the Shift lock key that occupies the same position on the keyboards of mechanical typewriters. An early innovation in mechanical typewriters was the introduction of a second character on each typebar, thereby doubling the number of characters that could be typed, using the same number of keys. The second character was positioned above the first on the face of each typebar, and the shift key caused the entire type apparatus to move, physically shifting the positioning of the typebars relative to the ink ribbon. Just as in modern computer keyboards, the shifted position was used to produce capitals and secondary characters.
Because the shift key mechanism on a mechanical typewriter requires more force to operate and is usually operated by the little finger on the left hand, it was difficult to hold the shift down for more than two or three consecutive strokes, therefore the introduction of the Shift lock key also helped out people with disabilities who could not hold down more than one key at a time. The Shift lock key was introduced so the shift operation could be maintained indefinitely without continuous effort. It mechanically locked the typebars in the shifted position, causing the upper character to be typed upon pressing any key.
As described above, the Caps Lock behaviour in most QWERTY keyboard layouts differs from the Shift lock behaviour in that it capitalizes letters but does not affect other keys, such as numbers or punctuation. Some early computer keyboards, such as the Commodore 64, had a Shift lock but no Caps Lock; others, such as the BBC Micro, had both, only one of which could be enabled at a time.
A version of Caps Lock that behaves like a traditional Shift lock does exist on certain layouts such as the French AZERTY. Some operating systems and window managers allow Caps Lock to be used for a similar function. This behavior of the Caps Lock survives, however, in German and Austrian QWERTZ keyboards.