Continuity editing refers to techniques used to create a sense of spatial and temporal coherence in films. There are two main categories - temporal continuity, which maintains a logical flow of time, and spatial continuity, which provides a clear physical narrative space. Specific techniques like match cuts, establishing shots, and eye line matches help preserve continuity and prevent disorienting the viewer. Ellipses, fades, and flashbacks can be used to convey temporal discontinuities like the passage of time.