ABSTRACT
This chapter aims to characterize the applicable supporting concepts of Boolean functions, nonlinear component of block ciphers, cryptography, watermarking and steganography. The important cryptographic properties which are utilized to investigate the quality of single and multiple output functions have likewise been characterized and talked about. Cryptology is the investigation of data security. In an era of digitally advanced communication, secure information security is an important component of any nation. The cryptology is additionally characterized by two branches: cryptography and cryptanalysis. Cryptography is the art/craft of writing to secure communication in insecure lines of communications. There are four essential elements of cryptography: confidentiality, data integrity, authentication and non-repudiation. There are a few methods for categorizing cryptographic algorithms. The modern cryptographic algorithms can be classified into three following broad categories: private/secret/symmetric key cryptography, asymmetric/public key cryptography and one way hash function. Cryptographic assaults manage the breaking of the security.
