The Pythagorean theorem is perhaps the best known theorem in the vast world of mathematics.A simple relation of square numbers, which encapsulates all the glory of mathematical science, isalso justifiably the most popular yet sublime theorem in mathematical science. The starting pointwas Diophantus’ 20 th problem (Book VI of Diophantus’ Arithmetica), which for Fermat is for n= 4 and consists in the question whether there are right triangles whose sides can be measuredas integers and whose surface can be square. This problem was solved negatively by Fermat inthe 17 th century, who used the wonderful method (ipse dixit Fermat) of infinite descent. Thedifficulty of solving Fermat’s equation was first circumvented by Willes and R. Taylor in late1994 ([1],[2],[3],[4]) and published in Taylor and Willes (1995) and Willes (1995). We presentthe proof of Fermat’s last theorem and other accompanying theorems in 4 different independentways. For each of the methods we consider, we use the Pythagorean theorem as a basic principleand also the fact that the proof of the first degree Pythagorean triad is absolutely elementary anduseful. The proof of Fermat’s last theorem marks the end of a mathematical era; however, theurgent need for a more educational proof seems to be necessary for undergraduates and students ingeneral. Euler’s method and Willes’ proof is still a method that does not exclude other equivalentmethods. The principle, of course, is the Pythagorean theorem and the Pythagorean triads, whichform the basis of all proofs and are also the main way of proving the Pythagorean theorem in anunderstandable way. Other forms of proofs we will do will show the dependence of the variableson each other. For a proof of Fermat’s theorem without the dependence of the variables cannotbe correct and will therefore give undefined and inconclusive results . It is, therefore, possible to prove Fermat's last theorem more simply and equivalently than the equation itself, without monomorphisms.