Sketching is the process of creating quick, rough drawings to explore ideas and concepts. In prototyping, sketching is often used in the early stages of design to quickly generate and iterate on ideas. Sketches can help designers visualize the layout and flow of a user interface, experiment with different design options, and communicate their ideas to stakeholders and team members. Sketching is an important part of the prototyping process because it allows designers to quickly explore and test ideas before investing time and resources into creating high-fidelity prototypes.