Each page contains a single game, implemented as a Java applet. If you haven't played these games before, you should start with the Introduction . It explains what a torus and Klein bottle are and shows you how to use the software. Once you've done at least the first two pages of the Introduction, you may play the six games in any order. Your experience with the games will depend heavily on how well your browser runs Java applets.
Most current browsers work well, and some older ones do too.
However, if your browser cannot run the games correctly, you may need to download a free replacement as explained below. If you still have problems, please consult the Frequently Asked Questions list in the technical support area of the Exploring the Shape of Space Web site . The Jigsaw Puzzle applet makes the heaviest demands on your computer and on your browser's Java engine. When you snap together two puzzle pieces, you may notice a couple seconds delay before the seam is erased and the applet is ready to continue. Please be patient, especially if you have an older computer.