What is the name of this visualization with a circle and internal arcs?
This is a chord diagram. It is usuallly generated from a square matrix like the one you have. This can be done with specific libraries at least in R (circlize package) and Python (plotly). It's also possible to do it with d3.js but apparently not so easily.
General advice: I find the &quot;X Graph Gallery&quot; websites quite convenient for exploring different types of graphs: R graph gallery, Python graph gallery and D3 graph gallery.