[nailer]

You can ask questions about crypto to real cryptographers on https://crypto.stackexchange.com. My layperson, 30 second understanding is:

- If you remember RSA, ECC replaces RSA because it has better performance.

- In ECC, public keys are points on a curve. There's two main types of EC curves:

- A Weierstrass curve looks like a pimple (classical ECC) - you'll see this in older crypto systems.

- An Edwards curve looks like a butthole - more popular these days, as it has less 'exceptional cases' on the curve which don't confirm to normal 'add two points together to get a third point' maths.

- 'Ristretto' turns out to be the ECC-based key derivation algorithm used by Polkadot cryptocurrency: https://wiki.polkadot.network/docs/learn-cryptography or https://ristretto.group/ and is based on Edwards curves.

The second answer (typical for Stack Exchange sites) summarizes it well):

> In the Ristretto group, 0 is a member of the group, while in Secp256k1 it is not.