Though concerned with the imaginary number i, often considered by many students to have no practical applications, such functions actually have many applications as well as deep significance in pure mathematics. I came to this field through the study of prime numbers. There are deep relationships between functions of a complex variable such as the Riemann Zeta function and the structure of the prime numbers. Through this connection I became deeply interested in the study of complex analysis, and this project has expanded my knowledge of this beautiful area. I will present some of the basic tools of complex analysis and their relationship to the prime numbers.