Differences between session vs session factory - Hibernate?

First of all, asking the difference between these interfaces doesn't make any sense. It seems like asking the difference between car manufacturing plant and car. A manufacturing plant is a place where the cars will be produced. Similarly, SessionFactory is an instance which will create Session objects.

SessionFactory is a factory class for Session objects. It is available for the whole application while a Session is only available for particular transaction.

Session is short-lived while SessionFactory objects are long-lived. SessionFactory provides a second level cache and Session provides a first level cache.