So let's look at how these are broken up into the four modules that make up

this course.

In the first module, we'll cover the core concepts of discrete math.

We'll first look at key integer concepts,

such as divisibility and prime numbers, and learn how to

use the Euclidean Algorithm to find the greatest common divisor of two integers.

We'll then learn about the principles of modular arithmetic, and with that in hand,

turn to the notion of multiplicative inverses in modular arithmetic world.

And see that we can extend the Euclidean Algorithm to find these inverses.

In the second module, we'll explore modular exponentiation, and

discover that exponential expressions that might take thousands of years to

calculate, if done directly, can often times be done very efficiently,

even by hand, in a matter of minutes.

Along the way, we'll also discover that exponents do not live in the same modular

world and the rest of the expression.

A fact that actually forms the basis from many of the cryptographic algorithms

that protect our most sensitive secrets.

Well then learn how the modulus of exponent is related to

the totient of the expression modulus, and how to calculate that torsion.

We'll finish this module by looking at discrete logarithms and see how they

behave very differently from the ordinary logarithms we're familiar with.