Cryptography / Classic ciphers
Lesson 2 of 25
The Caesar cipher
Julius Caesar shifted each letter three places: A becomes D, B becomes E. With only 25 possible shifts, it's broken by trying them all.
Key points
- Shift every letter by a fixed amount
- ROT13 is a Caesar shift of 13
- Try it in the Cipher Crack game
def caesar(text, k):
return "".join(
chr((ord(c) - 65 + k) % 26 + 65) if c.isupper() else c
for c in text.upper())Quiz · +10 XP
With a shift of 3, what does HELLO become?
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