Particle Swarm Optimization is an algorithm inspired by swarm behavior in nature that was invented by James Kennedy and Russell Eberhart. It is used to find the minimum value of a function by tracking the global best solution and each particle's self best solution. The algorithm works by initializing a random set of solution vectors and updating their positions based on their own experience and the experience of neighboring particles, getting closer to the optimal solution over many iterations similar to the way a flock moves together toward food sources.