There's a large range of tire brands and varieties to choose from, but one of the most basic delineations is asymmetrical vs symmetrical.

However, the basic difference between these two techniques is that symmetric encryption uses a single secret key while asymmetric encryption uses two separate keys.

Read this car news article from 2011-05-19. What are the differences between asymmetrical and directional tires?

The key distinction is between symmetrical and asymmetrical mysteries. A mystery is symmetrical if its negation is just as unexplainable as the initial mystery itself.