(Disassemble the Vue core modules one by one, write the underlying source code by hand, refuse to talk on paper, and take you to build your own Vue framework! This set of tutorials will take you deep into the bottom layer of the handwritten responsive data system, the bottom layer of the handwritten template compilation system, the bottom layer of the handwritten virtual DOM, and the diff algorithm. The explanation really allows you to improve your programming background and reach the intermediate and advanced front-end standards. This tutorial takes both Vue2.0 and 3.0 into account, focusing on the underlying differences between the two, and trying to let you understand each core mechanism.)