The MouseEvent interface represents events that occur due to the user interacting with a pointing device (such as a mouse). Common events using this interface include click, dblclick, mouseup, mousedown.
A pointer is a hardware agnostic representation of input devices (such as a mouse, pen or contact point on a touch-enable surface). The pointer can target a specific coordinate (or set of coordinates) on the contact surface such as a screen.
The ProgressEvent interface represents events measuring progress of an underlying process, like an HTTP request (for an XMLHttpRequest, or the loading of the underlying resource of an <img>, <audio>, <video>, <style> or <link>).
The server-sent event API is contained in the EventSource interface; to open a connection to the server to begin receiving events from it, create a new EventSource object specifying the URI of a script that generates the events. For example:
The PromiseRejectionEvent.promise read-only property indicates the JavaScript Promise which has been rejected. You can examine the event's PromiseRejectionEvent.reason property to learn why the promise was rejected.
The PromiseRejectionEvent.reason read-only property is any JavaScript value or Object which provides the reason passed into Promise.reject(). This in theory provides information about why the promise was rejected.
The onvrdisplayconnected property of the SpeechSynthesis interface represents an event handler that will run when a compatible VR device has been connected to the computer (when the vrdisplayconnected event fires).