This document discusses applying and modifying slide transitions in PowerPoint presentations. It explains that transitions define how slides are displayed and can be added or modified using the Transitions tab. The tab contains options to select transition types and set timing properties like speed and sound. Transitions can be applied to individual slides or all slides at once. They can also be removed by selecting None as the transition type or No Sound for the transition sound. The document provides step-by-step instructions for adding, modifying, and removing transitions and includes examples and practice activities.