The word ‘Algorithm’ is Latinized of Al- Khwarizmi. Muḥammad ibn Mūsā al-Khwārizmī was a Persian mathematician, astronomer and geographer who lived during the 8 A.D. century. He was also a scholar in the House of Wisdom, in Baghdad. In this talk we will explain how does a computer perform a given task? Algorithm is a necessity for each task a computer does. We will discuss what an algorithm might be. This is a philosophical question. We will discuss A. Church and A. Turing theses on definition of algorithm. Furthermore, we will explain a number of important and powerful algorithm that have ushered us to this exciting era. Among these algorithm is Stable Marriage Algorithm, Deep Machine LeaningAlgorithm, RSA Algorithm, Greedy Algorithm, Simplex Algorithm, and Metropolis Algorithm.