My name is Mark, the manager of Inflearn. I recently wanted to create my own household account book using a spreadsheet, so I took this course. I think it is a very clean and good course. The knowledge sharer's voice and recording quality are also excellent. It covers basic functions used in Excel and spreadsheets, and I felt like I was organizing things just by listening to the course. I would highly recommend it to those who are learning spreadsheets before Excel.