# Fundamentals of Cryptography

Since earliest history, man has had secrets to protect. As early as ancient Egypt, people were devising ways to exchange secret data. The art of encryption has evolved over time and played a vital role in history.

This article will explore modern cryptography techniques and look at how they are applied in computing technology today.

## Cryptography Basics

Cryptography is the art of taking information that is understood, changing it into something that is not understood, and then back again. Information that is understood and meaningful is called plaintext. When this information is subsequently encrypted, it becomes known as cyphertext.

The process of data encryption is often illustrated as f(x) = y. In other words, if we apply function f() to value x then we get value y. Although is seems very simple, it is an accurate depiction of the process of encrypting data. All encryption involves three fundamental elements. A Secret which is something needing protection, an algorithm which is basically a mathematical operation, and a key which is a secret that makes the whole thing possible. A simple example is below.

Ekey{data} = Dkey{data}

In order for two entities to encrypted data, both entities must agree on two vital pieces of information, the algorithm to be used the key.