Eventually each chip needs to be wrapped up in a package so it can be handled and shipped without damage. Most chips are housed in plastic packages that look like little black houses. (Chips are universally black; it's traditional.) The bare silicon is not simply dipped in melted plastic or sprayed with a covering because that would damage the delicate device. Instead, they're packaged clamshell style, as shown in Figure 4.9. First the chip is laid in the lower half of a plastic package, usually on a spot of glue to hold it still; then the upper half of the package is cemented to the bottom. A hollow cavity in the middle leaves room for the chip and avoids crushing it.