[fnoof]

Theodore Gray, cofounder of wolfram research, was responsible for notebooks I believe.

> I wrote the Notebook user interface for Mathematica and led the user interface group for over 20 years.

https://home.theodoregray.com/

[anonzzzies]

Wrote or thought of the concept are not the same.

[theodoregray]

See my long comment on another comment in this thread. I both thought of some of the key ideas, and implemented them.