[0]: https://andrea.corbellini.name/2015/05/17/elliptic-curve-cry...
Another, slightly more topical / simple explanation [0] was posted by Cloudflare almost exactly 6 years ago, I still point people to it as well.
[0] https://blog.cloudflare.com/a-relatively-easy-to-understand-...
[0]: https://andrea.corbellini.name/2015/05/17/elliptic-curve-cry...