This page demostrates the use of the OpenLayers UTFGrid Controls. When the selected event is triggered, the underlying feature attributes are shown on the right.
UTFGrids can be used to output highly optimized feature "hit grids". The UTFGrid encoding scheme encodes interactivity data for a tile in a space efficient manner. It is designed to be used in browsers for interactive features like displaying tooltips without having to hit the server for an "info query".