The wikidiagrams have an information button that appears at the top left when you hover over the diagram. Hover over the button for more information.
Wikidiagrams tracks the different hover zones using colours. If you want to see all the zones for a diagram, click on 'zones' and hover over the "All" zones box which has a rainbow stripy background.
An example graph - Showing bug counts in Audacity software
This graph is made of several elements that can be combined and customised. One notable feature is that the graph combines bars that are at regular intervals, for the months, with stars for events (releases of the software) that may be at any time.
The bars and stars have hover tooltips. These give more information - the actual values the bars or stars represent. The tooltips have optical stability. The information box mostly moves smoothly as you move the cursor, making it easier to read.
An example graph - An audio waveform
This is a line graph with the ability to pan and zoom. As you zoom in the line becomes thicker, making up for there being 'less of it', and blobs indicating specific points the curve goes through fade in.
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