Remember this from the early internet?
Flash shaped many early web animations and games. Adobe ended Flash Player support at the end of 2020; current web projects should use supported web technologies.
What does Flash mean?
Flash was an Adobe technology for interactive web content, games and animations. The Flash Player has no longer been supported since the end of 2020.
AN EXAMPLE IN PRACTICE
Where you might encounter it
In the past, a company website might have included an animated Flash homepage or a Flash game. The browser needed an additional plug-in for this. Today, such ideas can be implemented using supported web technologies; old Flash files are not automatically compatible.
Further sources
From NetzTurm Decode. Clear explanations with historical context.