Gets the distance, in pixels, that a document has scrolled horizontally.
The distance the document has been scrolled.
When you scroll a document horizontally, some content is moved outside the view of the display area. The pageXOffset property returns the difference between the first pixel in the content and the first pixel currently in view.
The value of the pageXOffset property is negative when the base direction of a document is set to display content in right-to-left order. For more information, see W3C Tutorial: Creating HTML Pages in Arabic, Hebrew and Other Right-to-left Scripts.