Seed dispersal is the way seeds get away from the parent plant to a new place. "Dispersal" means to spread or scatter. The basic idea is as follows. Plants, obviously, cannot move after they have put down roots. It follows that it is an evolutionary advantage to get their seeds away from the parent plant. If the seeds take root nearby they will compete with each other and the parent plant. Also, a species is more likely to survive when its members are widely spread. This is because local disasters still leave plants in other places.