Виртуальный Дом объяснил
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
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