Pops are little programs that live in a 2d world.
Pops can eat chemicals present in their square. Eating gives the Pop energy. If the Pop runs out of energy it dies.
Pops can look at their surroundings. This allows them to see how much food is available in nearby squares, for example.
Pops can move to any adjacent square.
Pops can reproduce. A Pop's offspring is an imperfect copy of its parent. In other words, Pops mutate.
A world is initialized with random Pops. Almost all randomly generated Pops are not capable of surviving. If all the Pops die, or no reproduction happens for a while, the world is destroyed and replaced.
With the current version, you will likely need to wait a while for something interesting to happen...