How do academic disciplines use PowerPoint? This project analyzed PowerPoint files created by an academic publisher to supplement textbooks. An automated analysis of 30,263 files revealed clear differences by disciplines. Single-paradigm "hard" disciplines used less complex writing but had more words than multi-paradigm "soft" disciplines. The "hard" disciplines also used a greater number of small graphics and fewer large ones. Disciplines identified by students as being more effective users of PowerPoint used larger images and more complex sentences than disciplines identified as being less effective in this regard. This investigation suggests that PowerPoint best practices are not universal and that we need to account for disciplinary differences when creating presentation guidelines.