Introduction: This course introduces in detail the origin, advantages and reasons for its widespread popularity in the mobile era. It introduces the functions and operating skills of the software through examples one by one, helping designers who have not been exposed to sketch quickly get started with this design tool, and people with no design background can also use it to learn the most basic operations and create simple design works. Teacher's practical lesson "Sketch Selected Case Collection of App Interface Design Tools" has also been launched: coding.imooc.com/class/199.html