Cryptography

The mathematics that keeps your passwords, bank transactions, and private messages safe from everyone on the internet. Without it, every connection you make would be as private as shouting across a crowded room.

// TLS handshake — how Alice talks to Bob privately over a public internet
Alice
Public key: 0x3fa2...
Private key: SECRET
Encrypted ciphertext ↔
Public internet (anyone can see this)
Bob
Public key: 0x9c1b...
Private key: SECRET
Plaintext
"Transfer $500 to Bob"

AES-256
Ciphertext
5a8f3b2c1d9e4f7a0b6c8d2e5f1a...