What is a Sketch in the context of CAD design?

In the context of CAD design, a sketch is fundamentally a profile that consists of 2D geometric shapes. It serves as the basis for creating more complex 3D models. A sketch can include lines, arcs, circles, and other basic shapes that define the outline or cross-section of a part. This 2D geometry is essential for tasks such as extruding or revolving to create three-dimensional objects.

Understanding this concept is crucial because sketches are often the first step in the design process, allowing designers to visualize and manipulate their designs before adding further details or converting them into three-dimensional forms. While other options mention different aspects of CAD tools and features, they do not encapsulate the core definition of what a sketch is in CAD modeling.