What exactly differentiates Vipassana from Samatha meditation?

What are the key aspects of Vipassana that are not present in Samatha? What is the main difference in the method from a meditator's perspective? Labeling emotions and feelings are part of samatha or vipassana? Does Vipassana allows emotions to rise more freely to check it for what it is while Samatha tries to avoid paying attention to it by returning to the breath process?