Drivers: The primary trends that will affect the world in which your company does business.
Uncertainties: The primary issues that will affect the rate of change or acceptance of your business trends.
Watchpoints: Events or directions that may signal the coming to pass of a particular scenario.
Weak Signals: Small-scale trends that could wreck your planning assumptions if they grow into big ones.
Wildcards: Utterly unpredictable events or trends that will totally null and void your scenario.