A review on steganography and cryptography

Today´s information world is a digital world. Data transmission over an unsecure channel is becoming a major issue of concern nowadays. And at the same time intruders are spreading over the internet and being very active. So to protect the secret data from theft some security measures need to be taken. In order to keep the data secret various techniques have been implemented to encrypt and decrypt the secret data. Cryptography and Steganography are the two most prominent techniques from them. But these two techniques alone can´t do work as much efficiently as they do together. Steganography is a Greek word which is made up of two words Stegano and graphy. Stegano means hidden and graphy means writing i.e. Steganography means hidden writing. Steganography is a way to hide the fact that data communication is taking place. While cryptography converts the secret message in other than human readable form but this technique is having a limitation that the encrypted message is visible to everyone. In this way over the internet, intruders may try to apply heat and trial method to get the secret message. Steganography overcome the limitation of cryptography by hiding the fact that some transmission is taking place. In steganography the secret message is hidden in other than original media such as Text, Image, video and audio form. These two techniques are different and having their own significance. So in this paper we are going to discuss various cryptographic and steganographic techniques used in order the keep the message secret.