Plaintext vs plain text

I'm trying to figure out how to use the word plaintext when it comes to cryptography.

I see different variants of it. Some people use the single-word variant: plaintext.

Others type it as plain text, 2 words.

What is the correct way to use it? Should it be 1 word or 2? And why is this the case?

Does the same go for ciphertext?

Solution 1:

If you want to refer to an unencrypted message, you should use 'plaintext' as this is (as Jim Mack and Hot Licks say) a term of art used in cryptography to refer to such messages (you can think of how you would use the word 'cyphertext' when refering to an encrypted message).

If you want to refer to the media type that indicates text containing no formatting commands or directives of any sort you should use 'plain text'