The zooming and scrolling feature enables the user to zoom into an area of the chart so the data is shown in greater detail. For performance reasons only the visible image chunk is requested from the server-side. However, the user can scroll into view other parts of the chart data and the requested image chunks are automatically loaded via ASP.NET 2.0 callback requests on the fly.
The user can perform the zooming / scrolling either manually or programmatically.