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

Vue 3 — modern Composition API. Vue 2 — traditional Options API.

Vue 2:

• Options API.
• Larger bundle.
• No built-in TypeScript.

Vue 3:

• Composition API.
• Smaller bundle.
• Better TypeScript support.

1// Vue 2
2data() { return { count: 0 } }

1// Vue 3
2const count = ref(0)

Key differences:

• Vue 2 — Options API.
• Vue 3 — Composition API, faster, smaller.