Cryptography is the art of devising codes and ciphers

Cryptography is the art of devising codes and ciphers, and cryptoanalysis is the art of breaking them. Cryptology is the combination of the two. In the literature of cryptology, information to be encrypted is known as plaintext, and the parameters of the encryption function that transforms are collectively called a key.
Cryptology took on many forms in the centuries between the fall of Rome and the dawn of the Industrial Age. By the late 19th century, with the advent of the telegraph and wireless radio, cryptology took its permanent place as an important component of commercial, military and diplomatic communications. Rudimentary mechanical and electromechanical encoding inventions developed at the turn of the 20th century and through World War I laid the foundation for stronger and more efficient cipher devices.
With the dawn of the computer age, the possibilities for encryption methods and devices expanded exponentially. Machines with blazing fast computing power gave cryptographers the ability for the first time to design complicated encryption techniques.
The next great evolution in cryptology came with the introduction of microprocessor-powered computers. The rapid deployment of increasingly powerful desktops quickened the pace of cryptographic development, since even a moderately skilled computer user could break many of the algorithms in use.
Cryptology is more deeply rooted in every part of our communication and computing world than when it was first employed by ancient peoples. We use it to protect everything from e-mail to e-commerce transactions to personal diaries. As our dependency upon technology increases, so too will our dependency upon cryptography. After all, we all have things we want to keep secret.