Xaw3d is an enhanced version of the MIT Athena widget set for the X Window System. Xaw3d adds a three-dimensional look to those applications with minimal or no source code changes. Xaw3d-devel includes the header files and static libraries for developing programs that take full advantage of Xaw3d's features.

You should install Xaw3d-devel if you are going to develop applications using the Xaw3d widget set. You'll also need to install the Xaw3d package.