Why is the Virtual DOM faster than the regular DOM?

The Virtual DOM is faster than the regular DOM because of how and when updates happen.

Here's the difference:

---

#1. The regular DOM

When you change the DOM directly (for example, through document.querySelector().innerText = '...'), the browser immediately:

• recalculates layout (reflow)
• performs a repaint
• updates the actual pixels on screen

Even small changes trigger heavy processes, especially with multiple updates.

---

#2. The Virtual DOM

This is a lightweight JS copy of the real DOM kept in memory. Frameworks (for example, React) first update this copy, then:

• compare the new and old versions (diffing)
• calculate the precise changes
• make one minimal real update to the DOM

---

#Why this is faster:

• there is no unnecessary reflow/repaint: they get deferred
• changes are grouped and applied at once
• only what actually changed gets touched
• it saves the browser engine's work

---

#Summary:

---

Conclusion: The Virtual DOM speeds up the interface through a smart intermediate layer that reduces the load on the real DOM and the browser. This makes animations, re-renders, and interactions noticeably smoother.