Steganography is the art and science of hiding a secret message, file, or data within an ordinary, non-secret file or message, known as the carrier or covertext. Unlike cryptography, which scrambles a message to make it unreadable but does not hide its existence, steganography's primary goal is to conceal the very fact that a secret communication is occurring. This is often achieved by subtly altering the data of a carrier file, such as an image, audio, or video file, in ways that are imperceptible to human senses, for instance, by modifying the least significant bits of pixel data in a picture. In cybersecurity, this technique can be used by malicious actors to exfiltrate data or deliver malware undetected, or by legitimate parties to protect sensitive communications from surveillance.