http://www.dougrice.plus.com/dev/graphs/resizeImage.html - resize image in a web page
https://wavedrom.com/tutorial.html
https://www.circuit-diagram.org/editor/
https://www.qsl.net/wd9eyb/klunky/home.html
http://www.cuneytyilmaz.com/prog/jrx/jrx.nongecko.html#
draw.io https://app.diagrams.net/
https://svg-edit.github.io/svgedit/
https://www.rapidtables.com/tools/pie-chart.html
https://www.w3schools.com/colors/colors_mixer.asp
https://docs.wokwi.com/?utm_source=wokwi - multi board simulator
http://www.dougrice.plus.com/nascom2/JavaScriptNascom2/jsnascom.html - nascom 2
http://www.dougrice.plus.com/g.htm
https://www.sitepoint.com/best-javascript-charting-libraries/
HTML has the canvas tag which needs JavaScript to plot graphs.
These light weight in-line graphs use JavaScript and the Canvas tags. They are examples.
http://www.dougrice.plus.com/dev/graphs/graph1sample.htm - experimental Bar Chart, line and step line.
http://www.dougrice.plus.com/dev/graphs/graph1pie.htm - experimental Pie Chart
http://www.dougrice.plus.com/dev/graphs/graph1nodes.htm - animation. Tips: Use a semi translucent rectangle to fade the graph.
http://www.dougrice.plus.com/dev/graphs/graph1portLed.htm - Thommy Thorn used a canvas for his Nascom 2 web page.
I was told about FLOT a long time ago: https://www.flotcharts.org/
Using FLOT: http://www.dougrice.plus.com/dev/dtmfCode/pcm2/flotscope.htm
This page uses flot. It models telephone lines and shows the results as an animation:- http://www.dougrice.plus.com/dougnapTheory/flot/a_artline4W.htm