The uses of the instructor-driven master classroom are limited only the faculty's creativity. Pre-packaged instructional materials are available, or faculty can develop materials themselves. Presentation software can be used to organize and present lecture notes, which can easily be enhanced with clip art and symbols. Faculty can spend class time facing the students rather than the chalkboard and increase the lecture's organization and legibility. Many classroom applications can be derived from word processing, spreadsheet, statistical, and database software. An English professor may use a word processing package to demonstrate sentence structure or an accounting professor may use spreadsheet software to show students how to calculate annuities. A biology professor may use an authoring program to create an application incorporating animation, still photos, and a movie to demonstrate the stages of mitosis.