The Web Layer

The Web Layer is, by default, the top layer in your Layers Panel. Anything that you do in your Document Window that involves the Web Tools will be placed on this layer. It cannot be duplicated, deleted, shared, or renamed but it can be moved. You can turn visibility of Web Layer content on or off by toggling its visibility icon in the Layers Panel or by clicking the Web Layer Show/Hide buttons at the bottom of the Toolbox.

These buttons will become very useful if your web content is complex and you need to see your graphics without the distraction of Slices and Hotspots.