There are many applications that can be used to present information to large or small audiences, including the ubiquitous Microsoft Office PowerPoint, Mac's Keynote, Microsoft Visio, and Adobe DC.
Presentation tools may be used to convey information online as well. Camtasia Studio, Explain Everything and Doceri allow for video display, and the free, web-based tool Haiku Deck approximates a presentation format with the ability to embed graphics and videos.
Sharing Your Presentation Online?
If you're teaching online, it's best to CONVERT your narrated PowerPoint into a movie file. Below is a guide to help you do that.