809
xkcd #2912: Cursive Letters
(imgs.xkcd.com)
Alt text:
๐ ๐ฝ๐ฑ๐ฒ๐ท๐ด ๐ฌ๐ช๐น๐ฒ๐ฝ๐ช๐ต ๐ ๐ฒ๐ผ ๐น๐ป๐ธ๐ซ๐ช๐ซ๐ต๐ ๐ฝ๐ฑ๐ฎ ๐ถ๐ธ๐ผ๐ฝ ๐ฏ๐พ๐ท ๐ฝ๐ธ ๐๐ป๐ฒ๐ฝ๐ฎ, ๐ฝ๐ฑ๐ธ๐พ๐ฐ๐ฑ ๐ต๐ธ๐๐ฎ๐ป๐ฌ๐ช๐ผ๐ฎ ๐บ ๐ฒ๐ผ ๐ช๐ต๐ผ๐ธ ๐ช ๐ผ๐ฝ๐ป๐ธ๐ท๐ฐ ๐ฌ๐ธ๐ท๐ฝ๐ฎ๐ท๐ญ๐ฎ๐ป.
Although cursive has a unified design, everyone writes cursive a little differently. The idea is that cursive is designed to write whole words in a single stroke. The concept of a secure signature in cursive is that the more work a single stroke is, the more uniquely a person writes it.
That is to say, even though you may have the same name as someone else, it's extremely unlikely that a person can copy your nuances precisely enough to forge your signature on the fly. It isn't a perfect system, but it's easy enough to verify a signature that people could do it before technology was around to aid that process.
That concept is also why they say the actual design of your signature is less important than the consistency of doing it the same every time.
There was some guy years and years ago who tried to see how ridiculous he could make his signature and have a store still accept it. As I recall he got to the point of drawing pictures on the receipt. Eventually he tried to buy something expensive like a TV for +1000 bucks before someone finally said something.
Of course now that search engines suck I'm having trouble finding the writeup he did.
At one time illiterate people could just mark an X. The security of a signature isn't really in it's uniqueness or it's relationship with your name. Security of a signature is down to the fact that you could to prison for forgery if you fake someone else's signature.