Steganography is a method of hiding data in another media type so the very existence of the data is concealed. Steganography is mainly accomplished by hiding messages in graphic images. The least significant bit of each byte of the image can be replaced with bits of the secret message. This practice does not affect the graphic enough to be detected.
Steganography does not use algorithms or keys to encrypt information. This is a process to hide data within another object so no one will detect its presence. A message can be hidden in a WAV file, in a graphic, or in unused spaces on a hard drive or sectors that are marked as unusable. Steganography can also be used to insert a digital watermark
on digital images so illegal copies of the images can be detected.
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