Cryptography or cryptology from Greekkryptós, meaning "hidden, secret" and graphein, meaning "to write" or logia, meaning "study". It is the practice and study of techniques for secure communication in the presence of third parties called adversaries (Stallings, William, March 2013). More generally, cryptography is about constructing and analysing protocols that prevent third parties or the public from reading private messages. Various aspects in information security such as data confidentiality, data integrity, authentication, and non-repudiation are central to modern cryptography.
Steganography is the practice of concealing a file, message, image, or video within another file, message, image, or video. The word steganography combines the Greek words steganos, meaning "covered, concealed, or protected," and graphein meaning "writing" (wikipedia). Steganography takes cryptography a step further by hiding an encrypted message so that none suspects it exists. Ideally, anyone scanning your data will fail to realise it contains encrypted data. It is in an instinct of human nature to pass along information and to reserve said information for designated eyes only (S Dutta , 2016).
Neither Steganography nor cryptography alone is a good solution for data secrecy from the attacks. But if these methods are combined, the system may provide more security to the data. If a message is encrypted and hidden with a steganography method, it provides an additional layer of protection and reduces the chance of the hidden message being detected. This combinational methodology will satisfy the requirements such as capacity, security and robustness for secured data transmission over an open channel.