How Is Cryptography Used Today?

           Cryptography or cryptology is a Greek word that means 'hidden'. The verb form of the word, interestingly means 'write' and the term eventually stands for the exclusive study of message secrecy. Today, cryptography has become a branch of information theory and is used within a mathematical approach to study the transmission of information from place to place. The science of cryptography involves communication in the presence of adversaries. It even enhances the spheres of engineering and pure mathematics. It plays a very important role within the spheres of information technology, authentication and access control.

           Cryptography involves the hiding of the specific meaning of messages, but not their existence. The study also contributes to the development of computer science, particularly in the techniques used in network securities. It is crucial in application in the spheres that involve extensive and sensitive levels of access control and information confidentiality. Cryptography is also used in ATM cards and computer passwords and even within the world of electronic commerce. The hidden numbers that are a part of sensitive information that is also customer specific in the application of the various identification codes like the PIN and TIN numbers issued to customers by the credit card companies and the banking institutions, depend upon the effective use of cryptography.

The word cryptography in Greek means "secret writing". However, the term today refers to the science and art of transforming messages to make them secure and immune to attacks. The original message before being transformed is called plain text. After the message is transformed, it is called cipher text; an encryption algorithm transforms the plain text to cipher text. A decryption algorithm transforms the cipher text back to plain text. The sender uses an encryption algorithm, and the receiver uses a decryption algorithm.


The term cipher is also used to refer to different categories of algorithm in cryptography. This is not to say that every sender-receiver pair needs its very own unique cipher for a secure communication. Instead, through the use of public ciphers with secret keys, one cipher can serve millions of communicating pairs. A key is a number (value) that the cipher, as an algorithm operates on. To encrypt a message we need an encryption algorithm, an encryption key and the plain text. These create the cipher text. To decrypt a message, we need a decryption algorithm, a decryption key, and the cipher text. These reveal the original plain text. In cryptography the encryption or decryption algorithms are public; the keys are secret.

Cryptography is still used today with big companies when they want info to be transmitted electronically to somewhere else they would often use cryptography so they will not be deceived in anyway