diff --git a/README b/README
index 0a00d87..9731aa9 100644
--- a/README
+++ b/README
@@ -12,6 +12,15 @@ sending a swarm of add_particle packets to the client (individually for
 each particle) BUT it could be done much more efficiently in the engine
 by sending a single add_particlespawner_advanced packet to the client.
 
+The key difference from this API compared to the standard particle
+spawner one is that you can define the particle's parameters as a
+linear function of a constant, time, and 12 random variables.  The
+12 random numbers are enough for each of the original random variables
+to have an independent/uncorrelated random value (i.e. you can implement
+a standard particle spawner's behavior using the advanced one) but
+interesting things happen when you reuse a single random value between
+different parameters.
+
 Included are a bunch of demo nodes, each of which creates a special
 particle effect that cannot be achieved with ordinary particlspawners
 every 2 seconds.  Use a /giveme command to give yourself demo nodes: