This book provides a selection of chapters on the subject of steganography. Steganography is the practice of undetectably altering a digital work to embed a message. The undetectability of the message in the altered work is an essential property of steganography, whereas the required alterations in the work may be perceived as long as the hidden information is undetectable and therefore also undecipherable by non-authorized parties. The design of a steganographic algorithm concerns the properties of the communication medium or channel; the cover work, usually in digital format; and the functions of embedding and decoding the message. As cybersecurity becomes increasingly essential to communications worldwide, hidden or undetectable communication provided by enhanced steganography techniques enables the secure information sharing required by many applications. For business, governmental, or personal sharing of information via communication networks, countermeasures need to be taken to ensure that a third party is unable to detect the existence of a message embedded in the work and to avoid even attempts at decoding the information without the authorization of the sender. The property of undetectability of steganography along with cryptographic techniques has derived secure information schemes in the literature and has been applied in practice. The issues and properties of steganography have been investigated by scientists and practitioners in order to evolve techniques to improve security while sharing information on the open network. This book offers chapters on steganography ranging from definitions to the basics issues and properties, scientific research on diverse techniques, applications for a variety of areas (cybersecurity, military or defense, law enforcement, healthcare, financial services, etc.), and discussions on future applications and current research on the topic.