Drag-and-drop is a popular and easy-to-learn pointing gesture: move the pointer to an object, press and hold to grab it, “drag” the object to a new location, and release to “drop”.

D3’s drag behavior provides a convenient but flexible abstraction for enabling drag-and-drop interaction on selections. For example, you can use d3-drag to facilitate interaction with a force-directed graph, or a simulation of colliding circles.

Node.js is an event-based server-side JavaScript engine.