ABSTRACT
The topic of cryptography is of interest not only to computer scientists, electrical engineers, and mathematicians, it is of vital interest to everyone. Every time we log into a secure network, make an online credit card payment, have paychecks deposited directly into our checking accounts, or worry about hackers accessing our private information, we should be concerned with cryptography. Our finances, our jobs, and our social lives involve and rely upon information security. Accordingly, this chapter presents the basic concepts of cryptography and illustrates how it can be used to add security to transmitted messages and data. This leads us into the branch of mathematics termed number theory, the study of integers and their properties.
