RC4 is the encryption algorithm used to cipher the data sent over the airwaves. It is important that data is scrambled; otherwise, anyone could "see" everything using a sniffer. This includes all e-mails, Web pages, documents, and more. RC4 is a very simple and fast method of encryption that scrambles each and every byte of data sent in a packet. It does this through a series of equations using the previously discussed secret key.
RC4 actually consists of two parts: the Key Scheduling Algorithm and the Psuedo Random Generation Algorithm. Each part is responsible for a different part of the encryption process. However, before discussing the algorithm in detail, we need to understand what an array is.