The Virtual DOM is an in-memory representation of the actual DOM (Document Object Model). It is a lightweight, tree-like structure that is used to store the current state of the DOM. It is a copy of the actual DOM, and is used to compare the current state of the DOM with the desired state. Whenever a change is made to the DOM, the Virtual DOM updates itself to reflect the changes.
For example, when a user adds a new element to the DOM, the Virtual DOM updates itself to include the new element. Similarly, when the user removes an element from the DOM, the Virtual DOM updates itself to remove the element from its representation. This helps to reduce the amount of time required to update the actual DOM, as the Virtual DOM can be updated much faster than the actual DOM.