Particle-size distribution

Particle-size distribution is like a game of marbles. Imagine you have a big bowl filled with marbles of all different sizes. If you scoop out a handful of the marbles, particle-size distribution tells you the sizes and amounts of marbles in your handful. For example, if you have 4 small marbles, 8 medium-sized marbles and 2 big marbles, then the particle-size distribution of your handful would be 4 small, 8 medium, 2 large.