coins and private keys

Imagine owning a key that opens a shadow vault in a cosmic ledger where the human is a speck. A private key is that key. It is the secret value that proves you control the balance linked to a public key. The public key is the address other people use to see and send funds. There is a mathematical link between the two keys, so you can get the public key from the private key. You cannot find the private key from the public key. That asymmetry is the promise of cryptographic security. Coins do not live on your phone or on any device. The blockchain records balances that are associated with public keys. Those balances exist as entries in a distributed database that is copied across thousands of machines. Miners and validators help keep that database honest by validating transactions and adding blocks to the chain. When you sign a transaction with your private key you prove that you authorized a movement of funds. The signature does not move a file. The signature tells the network to update the balance record. Hardware wallets store private keys offline inside a secure device so you can hold the key without exposing it to the internet. A hardware wallet still does not hold coins because coins are just network balances. The device only signs transactions safely on your behalf. Self custody means you are the custodian of your own private keys. This gives you control but also gives you full responsibility. If you lose your private key you lose access forever unless you have a secure backup. Backups are often encoded as recovery phrases that can recreate the private key set. Keep backups offline, safe and secret. Share your public key freely when you want to receive funds. Never share your private key or recovery phrase with anyone. Understanding keys demystifies where value lives and how transfers occur. The system trades the comfort of banks for the stark responsibility of private secrets. The rules are simple and unforgiving. Learn the difference between public and private keys. Treat the private key like the last ember in a dead universe.