What is Virtual DOM and how does it differ from the regular DOM?

Virtual DOM is an abstract representation of the real DOM, used in modern frontend frameworks (such as React) to optimize interface updates.

Unlike the regular DOM, which is directly linked to the display in the browser and can be resource-intensive to update, the Virtual DOM is a lightweight copy of the DOM in memory. When the application's state changes, a new Virtual DOM is created, which is then compared to the previous version (a process called "diffing"). Minimal changes are then calculated to be applied to the real DOM.

This reduces the number of operations on the real DOM, improving performance and making interface updates more efficient.