Particles can birth more particles as they age. This is how you get fireworks (a main particle explodes, spawning 100 tiny colored children) or complex electricity.
Opening Particular for the first time can be intimidating. There are six main roll-down menus. Let's deconstruct them logically.
Integration. It works seamlessly with other Trapcode tools like Form (particle grid) and Mir (3D surfaces), and it is supported by every major Render Farm (RenderGarden, Deadline, etc.).