Eraser Tool

The eraser is basically a brush which erases pixels as you drag it across the image.
Pixels are erased to transparency, or the background colour if the layer is locked.

Background Eraser Tool

The background eraser tool allows you to remove the background colour from an image or layer.
When you click the image, the eraser samples the colour at the centre of the brush and erases this colour as you drag.
Options in the toolbar allow you to specify the type of erasure, colour tolerance and sampling method.

Magic Eraser Tool

The magic eraser tool erases all colours within a set tolerance. This is essentially
the same as using the magic wand and hitting Delete. Using this tool you don't need to drag � just click once.