S5 stands for Simple Standards-Based Slide Show System and is an XHTML-based file format for defining slideshows. It was created by Eric A. Meyer as an alternative to the browser-centric Opera Show Format. S5 is not a presentation program, but fulfills the same purpose in combination with a standards-compliant web browser. The text of an S5 presentation can be stored in a single XHTML file. This file contains several slides which are coded in the following way.