Cryptography, derived from the Greek words 'kryptos' meaning hidden, and 'graphein' meaning to write, is the practice of securing communication. It involves techniques for transforming information to make it unintelligible to all except those who possess special knowledge, often referred to as ‘keys’. The fundamental purpose of cryptography has always been to ensure confidentiality, integrity, and authenticity of information, though its role in history is multifaceted. It has been a tool for asserting power, a weapon in warfare, a shield for protecting personal privacy, and a means to secure financial transactions. Each advancement in cryptographic techniques has been a response to new challenges, whether they be in the form of political machinations, wartime strategies, or digital threats. As we journey through the history of cryptography, we will witness the growth of this art from its modest beginnings to the sophisticated methods of the modern era.
