[tim_hutton]

Not hidden in the knitting in the sense of the specific stitches (which is also very cool: https://www.popsci.com/story/diy/secret-code-messages-knitti...) but it seems she needed the knitting needle to insert the one-time codes (on a piece of silk) into a shoelace. Amazing story.

[velavar]

That was my first thought too. Different stitches such as knits and purls could serve very well as dots and dashes. Maybe that could've been too easily spotted.

[i_am_jl]

She transmitted her messages via radio, which allowed her to skip the messy business of smuggling knitted intelligence out of occupied France.

That being said, I'm 100% stealing the knitting-as-writing concept for a TTRPG campaign. It's just too cool of an idea to go to waste.

[joycian]

https://en.m.wikipedia.org/wiki/Quipu

[i_am_jl]

Thank you! I remember learning about this in an art history class decades ago, but I'd completely forgotten and I never would've remembered the name.