Reconciliation is a process in Reactjs for rendering the changes in the DOM by comparing the new virtual DOM tree with the old one. It is used to perform updates by handling component states, diff algorithms and the actual browser DOM updates.
Here’s generally how it works:
1. Whenever a react component’s state or props change, a re-render is triggered.
1. React builds a new virtual DOM tree (a lightweight copy of the actual DOM).
1. It then compares this new tree with the old one (diffing), and calculates the minimal number of steps to transition from the old tree to the new one.
1. After these differences (diffs) have been calculated, React updates only those objects in the real DOM that need to change. This process is called reconciliation.
1. The reconciliation process ensures that the Virtual DOM remains fast and efficient by reducing time complexity (O(n) instead of O(n^3)) and makes the whole process really fast.
React’s ability to perform updates in this way is one of the reasons it can provide a highly interactive and smooth user experience.
