inators</a>, an interaction net computational step can be defined as a constant time operation, and the model allows for <a href='parallel_computing.html'>parallelism</a> in which many steps can take place at the same time.</p>

<h3 id='agents'>1. Agents</h3>

<p>An <b>agent</b>(<i>a</i>) is a cell that has one <i>principal port</i> and a number of <b>auxiliary ports</b>(<i>n</i>). A pair of agents connected together on their principal ports is called an <i>active pair</i>. Graphically, principal ports are 