expand on data visualization guidance

[afeld]

In doing research for a 10x project on accessible data visualizations, a few points came up as accessibility principles that are particularly relevant for data visualizations:

• Use semantic HTML
• Ensure high contrast
• Don’t rely on only color to distinguish/identify items/values
• Include alt text and/or a caption that is objective and provides the amount of detail that is appropriate for the intended user
• Provide a fallback as a data table, audio description, or “audio graph”
• Ensure the visualization zooms properly
• Be careful with visualizations that require interactivity and/or animate

Would be good to incorporate this on the data visualization page. You can also check out the full synthesis notes from my research, but not sure if they will make sense to anyone else.

[afeld]

Worth noting: in the 10x project, we considered data visualizations to be "tables, charts, graphs, maps and diagrams". Seems like the page on this site defines them more narrowly.