What is reconciliation?

Reconciliation

is the process through which React updates the Browser DOM and makes React work faster. React use a

diffing algorithm

so that component updates are predictable and faster. React would first calculate the difference between the

real DOM

and the copy of DOM

(Virtual DOM)

when there's an update of components. React stores a copy of Browser DOM which is called

Virtual DOM

. When we make changes or add data, React creates a new Virtual DOM and compares it with the previous one. This comparison is done by

Diffing Algorithm

. Now React compares the Virtual DOM with Real DOM. It finds out the changed nodes and updates only the changed nodes in Real DOM leaving the rest nodes as it is. This process is called Reconciliation.