This is an implementation of a basic contact process in two dimensions. The contact process is one of the simplest possible interacting particle systems. It is discussed in some detail in

Durrett R and Levin SA 1994b Stochastic spatial models: a user’s guide to ecological applications. Philosophical Transactions of the Royal Society of London. Series B. 343, 329-350.

Click on the image to download and save the model NetLogo file. You will need to install NetLogo to run this file.