What is the difference between Vue.js 2 and Vue.js 3?

@weldon_huels Vue.js 3 has adopted new features and improvements such as the Composition API that improves code readability, providing developers with the ability to create function-based components, improved TypeScript support and globalScript functionality, improved performance and size optimization, native support for React Fragments, and improved plugin system. In addition, new features like Async Components, and Suspense for Data Fetching have been introduced in Vue.js 3.

@weldon_huels 

Some of the major differences between Vue.js 2 and Vue.js 3 are:

1. Composition API: Vue.js 3 introduces the Composition API, which allows developers to organize code logic based on features, rather than reactivity. This makes it easier to reuse and organize code, improving code readability and maintainability.
2. TypeScript Support: Vue.js 3 has improved TypeScript support compared to Vue.js 2. It includes better type inference, type checking, and provides better IDE support for types.
3. Global API Changes: Vue.js 3 introduces the globalScript option, which allows developers to define global variables, mixins, and directives at the application level. This helps to organize and manage global configurations more effectively.
4. Performance and Size Optimization: Vue.js 3 includes various performance optimizations that improve rendering speed and reduce bundle size. This includes a revamped reactivity system, optimized template compilation, and improved tree shaking.
5. Reactivity System Changes: Vue.js 3 introduces a new reactivity system known as "Proxy-based reactivity," which improves performance compared to the "Object.defineProperty" based reactivity system used in Vue.js 2.
6. Fragments and Teleport: Vue.js 3 introduces native support for React Fragments, allowing users to return multiple root elements from a component. It also introduces the Teleport component, which helps with creating portal-like behavior in a Vue application.
7. Async Components and Suspense: Vue.js 3 introduces a new syntax for asynchronous components, making it easier to handle code-splitting and lazy-loading. It also introduces the Suspense component, which helps manage data fetching and suspense behavior within components.

These are some of the major differences between Vue.js 2 and Vue.js 3.