The gable is the triangular portion of the siding that forms between the edges of two roof fields. In high wind areas this gable end may require a house to have additional bracing, as a gable catching the wind can significantly increase the roof load. Because of this gable roofs are not as recommeded for hurricane areas, with the roof being more susceptible to peeling away in those extremely windy conditions.
You can find gable ends on Gable Roofs and Cross-Gable Roofs. While the Saltbox Roof might appear to have a gable end in fact it doesn't as a true Gable requires that both sides of the roof have the same pitch.