In standard database systems, you access your funds using a username and password. If you lose your password, a database administrator can reset it.
In blockchain networks, there is no administrator. Instead, security is maintained using Asymmetric (Public-Key) Cryptography.
### The Keypair Mechanism
Every Web3 account consists of a mathematically linked pair of keys:
1. **The Public Key (Address):** This is a long string of hexadecimal characters (e.g., starting with 0x on EVM chains). It is safe to share with anyone and acts as your account number where people can send tokens.
2. **The Private Key:** This is a secret signature key. It must never be shared. Anyone who gets hold of this key can sign transactions and empty your wallet instantly.
### One-Way Mathematics
The public key is generated from the private key using one-way mathematical operations (Elliptic Curve Cryptography). While it is easy to derive the public key from the private key, it is mathematically impossible to reverse the process and compute the private key from a public address.