The Magnifying Glass, or Zoom tool, can be used to get a closer, more detailed view of an image. This is very useful if you’re working in close with the fine details of a part of an image. When you activate the Magnifying Glass tool, you’ll have an option to select between 1x, 2x, 6x, and 8x magnification. You can click on the part of the image that you want the magnification to center on. This will not affect the actual image in any way, just how it appears on your screen. Once you zoom in, the magnifying glass will automatically switch back to whatever tool you were using before.
Not too much needs to be said that isn't sufficiently demonstrated by the illustration above. Compare it to the original-sized picture on the Eraser Tool page. With the Zoom Tool, you can get up close and personal with every pixel in your image! If you've got a shaky hand, or need to work with tiny details, the Magnifying Glass will soon become your best friend!