The drag-and-drop API is one of the coolest features of HTML. It helps us implement drag-and-drop features in web browsers. In the current context, we will be dragging files from outside the browser. On dropping the file(s), we put them on a list and display their names. With the files in hand, we could then perform some other operation on the file(s), e.g. upload them to a cloud server.

https://www.smashingmagazine.com/2020/02/html-drag-drop-api-react/