Webpages are normally arranged using a table structure similar to Microsoft Excel documents. "Carving" is the process of taking a single design file and carving it into manageable table cells. There are several things to consider before starting the carving process:
Neat Trick: Press Ctrl+A or click and drag your mouse from the top, left to the bottom, right of your screen. All elements that are in the foreground of this page will be highlighted. All graphics appear as blocks where text can be highlighted letter by letter.
The following is an example of a site that has a fixed width, a text-based navigation bar, and one block of content:

See design
See table layout
See carved images
Let's take a look at a site that stretches with the browser, contains several text elements, and utilizes both forground and background images.

See design
See table layout
See carved images