A timeline is a perfect tool for visualising complex information … and is sometimes quite complex itself. This example from evolutionoftheweb gives both. And it shows interesting details like the evolution of Flash and SVG over time.
Flash
SVG.
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This is interesting and it turns out to be a pretty bad and misleading visualisation. I was immediately hooked as I thought the graphs would depict the decline of Flash and the long winding road to ubiquitous SVG support in browsers and therefore on the web.
However this is simply not the case: The arrangement of browsers’ timelines is rather arbitrary and therefore the diagram for one technology could take on any shape. Choose e.g. the “evolution” of AJAX and then compare that to Java: you would think Ajax had a rough time and is on its way out as the colors fade out whereas Java seems so solid, which is a totally wrong picture.
Mostly it shows that browser version numbers increment faster these days. Additionally Flash is a plugin and is treated as just one technology and no other plugins are mentioned (and Java would be an OS-level technology rather than a browser’s), but for the present, even sub-devisions of CSS3 like animations or transforms are treated as separate entities that get their own line-chart.