From: Daniel Piechnick
Hi Lew. Outside of Photoshop, there's no such thing as a "slice". In Photoshop, use the Slice Tool to draw boxes on your image. Then click File > Save for Web, choose your settings (I use Jpeg, Quality 60), and click OK. This will then save each of those slices as a separate image. You can then just insert them into your web page like any other image.