Abstract
The complex numbers and the complex functions are main topics to go through the complex analysis. The complex analysis is a wide topic found in many areas of pure, applied and engineering applications. Therefore, many authors have tried to put their experience in this field that ignored by others. The present chapter aims mainly to cover some basic concepts for the beginners in the field of complex analysis, such as concept of complex number, idea of complex number, algebraic operations and more.
Keywords: Complex number, polar representation of complex number, complex number properties, roots of complex number, Cauchy theorem, generalized Cauchy theorem.