The word Steganography is derived from the Greek words Steganos meaning "covered" and graphy meaning "writing or drawing". It is also commonly known as 'Disappearing Cryptography'.
What is Steganography?
Steganography is the art and science of hiding information into covert channels so as to conceal the information and prevent the detection of the hidden message. Today, steganography refers to hiding information in digital picture files and audio files.
Steganography is defined as "hiding information within a noise; a way to supplement (not replace) encryption, to prevent the existence of encrypted data from being detected" . Steganography and Cryptography are cousins in the data hiding techniques. Cryptography is the practice of scrambling a message to an obscured form to prevent others from understanding it. Steganography is the study of obscuring the message so that it cannot be seen.
This tutorial is an elementary overview of some basic areas of steganography. It provides an introduction to steganography for those unfamiliar with the field. Specifically, the tutorial covers the history and basics of steganography, and looks at image files and how to hide information in them, and briefly makes mention of digital watermarking, and steganalysis - the process of detecting steganography. The tutorial walks through two example programs that hide text within an image.