I have spent most of my life creating slides for my presentations as well as my clients. In the beginning, is was a single Kodak Carousel projector with a 35MM slide in a tray that held 80 slides. Larger trays were available but they jammed with glass mounted slides.
Then I started using two (2) projectors so I could do dissolve.
Followed by stacks of three projectors to create animations. I won a huge contract with Toyota using 15 projectors for a 45-minute presentation. 1200 slides.
Soon microcomputers were adapted to control the projectors and then a small company created a software program call PowerPoint. It struggled for along time until it was sold to Microsoft. BOOM…
and now zoom is beta testing a modification that returns the presenter to be in front of a screen showing their slides.
I am an expert in PowerPoint creation. Look at some of my other courses to develop your presentation skills using PowerPoint.