Your guide to reactivity in Vue.js

Reactivity in Vue.js is a central feature that allows changes in application state to be automatically reflected in the DOM, enhancing user interface responsiveness. Vue 3 has improved upon the reactive system of Vue 2 by utilizing JavaScript's proxies, which act as wrappers around objects or functions to intercept operations such as getting and setting values. This new approach addresses limitations in Vue 2's reactivity, which relied on Object.defineProperty to track data changes. The introduction of proxies in Vue 3 allows for more efficient dependency tracking and change notification, facilitating a more seamless and declarative programming paradigm. By creating proxy objects, Vue 3 can automatically detect and respond to changes in data, ensuring that updates propagate throughout the application's components. This enhanced reactivity system is fundamental for developers to build reactive user interfaces and effectively manage state changes, supporting the creation of modern, dynamic web applications.