This page demonstrates how to build custom plotters with dygraphs. The plotter option allows you to write your own drawing logic. This can be used to achieve powerful customization. View source to see how the examples work.
Here a specialized plotter is used to draw a bar plot rather than a line plot:
Here a specialized plotter is used to combined four series into a unified "Candle" plot:
The plotter option may be set on a per-series basis to create mixed charts:
You can tweak the standard plotters list to achieve effects which would be difficult otherwise, e.g. drawing series with only confidence intervals and showing high/low bands only for some series.
See the smooth-plots demo for an example of a custom plotter which connects points using bezier curves instead of straight lines.