Some codes replace each letter with a symbol. The best known is the Pigpen cipher (Freemason's cipher): each letter is the piece of grid around it. A to I in a hash grid, J to R in the same grid with a dot, S to V in an X, W to Z in the X with a dot. Click the symbols in order to rebuild the message, or type a text to see it enciphered.

Key

Decipher

Encipher

In real life: dCode (Pigpen cipher, Templar cipher, Braille, semaphore), CyberChef. These symbol alphabets come up in treasure hunts, escape games and CTFs; there are variants (letter order, dot placement): if the message makes no sense, try another one.