Keynote was announced by Steve Jobs as an app created for him for his world-renowned presentations. (Previously Jobs had used the application Concurrence by Lighthouse Design.)
This is the box version of Keynote 1.0 from 2003. Keynote was sold as a separate application for about two years until it joined Pages as a part of Apple’s iWork suite of software tools.
In my opinion, Keynote has been far superior to PowerPoint and other presentation applications since its release. Keynote used 3D slide transitions and builds that take full advantage of OpenGL, the graphics system that is part of macOS. Keynote has always perfectly handled imported media since it supports all QuickTime formats available in macOS.
I have been a Keynote user since its beta release in 2003 and have seldom used other presentation formats.