Corn masa is a complex matter that requires knowledge, practice and skill. Masa could easily be one of the foundations for Mexican cuisine. In order to make it, one must use nixtamal, for the fresh or dried corn is no good for tortillas. Nor tamales nor any dish that requires masa for that matter.
The preparation of nixtamal involves a simple process but one that needs to be done properly. The nixtamalization includes soaking the corn kernels and then cooking then in an alkaline solution (of water with lime or ash) and allowed to soak for over 12 hours. During this cooking, corn changes its chemical and molecular structure, making it much easier to peel and grind it in a metate or a mill. And in this way masa can then be made. Though it is important to say that with such a diverse range of dishes, the masa needed will most likely be different from one to the next.