What is Nostr?

Public Key
npub1z3d3n82nydq9qkt3f38rt0mjhdxmacr4nchuszakczxgkrjx0rgs7gnslx
Profile Code
nprofile1qqspgkcen4fjxszst9c5cn34haetknd7up6eut7gpwmvprytper835g5au925
Author Public Key
npub1z3d3n82nydq9qkt3f38rt0mjhdxmacr4nchuszakczxgkrjx0rgs7gnslx