Conway's game of life
Conways's game of life is simulation of the evolution of a population of simple organisms. Every pixel represents one cell and can have one of 2 states: Present or empty, typically represented by 1 and 0, and an illuminated or black pixel. The rules for each generation are quite simple: The organism will be alive in the next generation if it either
Is alive and has 2 or 3 neighbors Is dead and has exactly 3 neigbors
An example implementation in BASIC can be found here: https://wiki.segger.com/BASIC_programming_language#Conway.27s_game_of_life