One thing we might want to do in computer graphics is to render large quantities of "sprites" such that we can recognize how they're moving & what that's meant to evoke.
The trick is to make repositioning & rendering each individual particle extremely cheap, so we can afford to render as many as we want!
Typically we draw them as small camera-facing "bilboards" to achieve this cheapness.
Updating each particle's position's cheap as long as they're not interacting.
1/2!
