If you are old enough to remember a time when if you were really lucky you might have access to a computer over a 9600 baud serial line connecting with a terminal, you may well have encountered the Compose key on DEC serial terminals (or in many other places). If you aren’t, I’ll have to explain what they are …
Imagine you have a US or UK keyboard, and suddenly have a need to enter an accented character (such as ü) – perhaps in a place name or perhaps you simply want to spell “café” properly for once. If you look at your keyboard you’ll find that the relevant characters do not appear anywhere. One of the solutions to this are the “dead letters” where certain symbols (such as “) work by putting the mark on the key over the next letter you type.
This apparently works well enough for those who enter such letters every other word or so, but I’m a monolingual Englishman who does not need them so often and I would rather have my quote key left alone thank you very much.
Now imagine a special key on the keyboard. Let us call it “Compose” for the want of any other name. You press it, and a fourth LED on your keyboard lights up. You can then enter any suitable two character sequence to generate accented characters or other symbols (½, «, ¡, ♯, ə, þ, etc.). Perhaps it might stretch your memory a bit remembering all the sequences, but you soon get used to much of it … it doesn’t take much memory capacity to remember that compose, u, ” becomes a ü, and that if you want anything with an umlaut on it, just use compose, whatever needs an umlaut, and “.
Back when I got started in IT, we had a bewildering variety of different types of keyboards with different layouts (and many of which were better by far for typing than most modern crud). For better or worse the IBM keyboard layout effectively won (the Macintosh keyboard is an IBM one with a few extra function keys and some of the modifiers relabelled). One of the big losses was the lack of a Compose key.
Let’s have it back!
Oh! And if you are going to have an “Alt GR” key to function as a “shift” key to enter funky symbols, please engrave the symbols on the front of the keys. You will notice that where the Shift key produces a different symbol, the different symbol is shown on the key – see the 1 key with ! shown.