The message-passing model might refer to discrete event system implementations of digital logic simulators. That is, you can think of the events as messages bet

The message-passing model might refer to discrete event system implementations of digital logic simulators. That is, you can think of the events as messages between logic gates and wires. See for example the simulator in SICP: https://mitpress.mit.edu/sites/default/files/sicp/full-text/book/book-Z-H-22.html#%25_sec_3.3.4 https://mitpress.mit.edu/sites/default/files/sicp/full-text/...