The main difference between cryptography and steganography is that while cryptography involves coding the message using an encryption key and sending it as cypher text, steganography involves hiding the intended message within a seemingly harmless message. Cryptography and steganography are similar in the sense that they are both techniques that are used to send information securely.
Cryptography can be defined as the science and art of secret writing. It dates back to 1900 B.C. The three types of cryptographic algorithms are Secret Key Cryptography (SKC), Public Key Cryptography (PKC), and Hash Functions.
Steganography can be defined as the science and art of hiding information in a way that prevents its detection. Some familiar stenographic methods include the use of invisible ink or forming a message using the second letter of each word in a large body of text. In the 21st century, steganography allows people to hide information within images or audio files.