Useful websites for simulation
The Society for Computer Simulation http://scs.org/
The Association for Computing Machinery ACM's special interest group in computer simulation, SIGSIM. http://www.acm-sigsim-mskr.org/
The Winter Simulation Conference governing board maintains a site at WSC. https://informs-sim.org/
also, see some wonderful "math visuals" at https://www.3blue1brown.com/