In this section I will be looking at the elementary teachings of Number Theory that I have learned while reading different Number Theory books. I will be initially following the teachings from the Underwood (1978/2008) book. This section will then be following the format of that book but it will not be confined to that format as I go through other elementary number theory books that contain a better distribution of the material. In the end, I hope that others will find this information useful beyond my own interest of this particular branch of Mathematics.