All files are read-only, so you can't accidently change anything. The size of Appendix A is more than 100K bytes. That makes it about 5 times larger than any other file in these pages. As a result, it will take a long time to load fully. Since the file is so large, it will be loaded into its own copy of your browser.
Most newer browsers have the capacity to spawn a second copy of themselves.
We are taking advantage of this technology to spawn a second copy of your browser and load Appendix A into that copy. This will allow you to keep Appendix A on your screen, in a separate window, while you view the rest of the Glossary. You may not, at first, notice this second copy of your browser. With some older browsers, it will be loaded onto your screen at the exact coordinates as your first copy. You simply need to move the Window box of the second copy to see the first copy underneath.