Plaintext is what encryption algorithms, or ciphers, transform an encrypted message into.
In cryptography, algorithms transform plaintext into ciphertext, and ciphertext into plaintext. These respective processes are called encryption and decryption.
The basis for using such a system is to ensure that the data can only be read by its intended recipient.
“If you are storing user data or sending any part thereof over the wire, make sure it is encrypted. Passwords and similar credentials should never be stored or shared in plaintext.”