The Element.clientWidth property is zero for elements with no CSS or inline layout boxes, otherwise it's the inner width of an element in pixels. It includes padding but not the vertical scrollbar (if present, if rendered), border or margin.
The Element.scrollTop property gets or sets the number of pixels that the content of an element is scrolled upward. An element's scrollTop is a measurement of the distance of an element's top to its topmost visible content. When an element content does not generate a vertical scrollbar, then its scrollTop value defaults to 0.
The Element.scrollWidth read–only property returns either the width in pixels of the content of an element or the width of the element itself, whichever is greater. If the element is wider than its content area (for example, if there are scroll bars for scrolling through the content), the scrollWidth is larger than the clientWidth.
The Gamepad.axes property of the Gamepad interface returns an array representing the controls with axes present on the device (e.g. analog thumb sticks).-
The Gamepad.index property of the Gamepad interface returns an integer that is auto-incremented to be unique for each device currently connected to the system.
The Gamepad.mapping property of the Gamepad interface returns a string indicating whether the browser has remapped the controls on the device to a known layout.
The Gamepad.timestamp property of the Gamepad interface returns a DOMHighResTimeStamp representing the last time the data for this gamepad was updated.
The GamepadButton interface defines an individual button of a gamepad or other controller, allowing access to the current state of different types of buttons available on the control device.
The GamepadButton.pressed property of the GamepadButton interface returns a boolean indicating whether the button is currently pressed (true) or unpressed (false).
The GamepadButton.value property of the GamepadButton interface returns a double value used to represent the current state of analog buttons on many modern gamepads, such as the triggers.
HTMLDocument is an abstract interface of the DOM which provides access to special properties and methods not present by default on a regular (XML) document.
The HTMLElement.offsetLeft read-only method returns the number of pixels that the upper left corner of the current element is offset to the left within the HTMLElement.offsetParent node.
The HTMLElement.offsetParent read-only property returns a reference to the object which is the closest (nearest in the containment hierarchy) positioned containing element. If the element is non-positioned, the nearest table cell or root element (html in standards compliant mode; body in quirks rendering mode) is the offsetParent. offsetParent returns null when the element has style.display set to "none". The offsetParent is useful because offsetTop and offsetLeft are relative to its padding edge.