Decrypting a substitution cipher, but with symbols instead of letters I'm trying to decipher a message encrypted by a substitution cipher (probably a monosubstitution). But the problem is, that we have symbols instead of letters (letters were substituted for random symbols). What would be the best way to decrypt such a message?

Thanks
Frequency analysis is the way to go. If your plaintext is in English then the letter "e" would (probably) be the most common letter in the text. A good technique would also be to look for repeated symbols. In the English language (and probably all other languages as well) there are many words with double letters (i.e. "kill", "hello", "symmetry"), so you can narrow it down what the word with the repeated symbol would be.