If you’ve used Windows for any length of time you’re probably familiar with entering special characters with the ALT+ method. For example, to enter “É” — Latin Capital Letter E with Acute, Unicode code point U+00C9 — you can hold down the ALT key and while continuing to hold it down, type 0201 on the numeric keypad, then release the ALT key. It doesn’t take long before you’ve memorized the characters you use frequently.
There are some problems with this method. The original PCs used CP437 (code page 437) keyboard mapping for English. When Windows came along, CP1252 (code page 1252) began to be used for keyboard mapping. If you use the ALT+ method with a three-digit code (the first digit non-zero), for example, ALT+201, you get “╔”— Box Drawings Double Down and Right, Unicode code point U+2554 — the character at CP437’s code point 201. If you add a leading zero (0) and then the number, ALT+0201, you get “É”, the character at CP1252’s code point 201. Confusing, right?
“Rightful liberty is unobstructed action according to our will, within the limits drawn around us by the equal rights of others. I do not add ‘within the limits of the law’; because law is often but the tyrant’s will, and always so when it violates the right of an individual.”
— Thomas Jefferson, in letter to Isaac H. Tiffany, April 4, 1819.