The virtual DOM (VDOM) is a programming concept where “virtual”, representation of a UI is kept in memory and synced with the “real” DOM by a library such as ReactDOM.
The virtual DOM is used for efficient re-rendering of the DOM
React aims to re-render the virtual tree only when the state changes
Uses 2 virtual trees (new and previous) to find differences and batch update real DOM
Whenever possible, does not update entire component in real DOM - only computes a patch operation that updates part of the DOM
React keeps a lighweight representaion of the Real DOM in the memory.
When you make some change, the virtual DOM only changes the specific
object in the dom instead all of the objects.
Virtual Dom understands which area needs to send the update and
avoids the other areas.