In today's data-driven world, Microsoft Excel has become an indispensable tool for professionals across various industries and Excel functions are very important in processing data and obtaining useful information for individuals, employees, and managers in order to make the right decisions. In this course, we will study 40 of the most important functions in Excel, with practical examples of their use. The course also contains all the Excel files explained in the various videos, and each file contains more than one sheet in order to apply the functions explained in the video. We intended to have all the functions for a certain type in one file together so that this file will be a reference for the student to know the types and methods of applying these functions.