What color indicates that a sketched geometry is under-defined in SolidWorks?

In SolidWorks, a sketched geometry that is under-defined is indicated by the color blue. This visual cue signifies that the sketch lacks sufficient dimensions or geometric constraints to fully define its shape and location. When a sketch is under-defined, it is susceptible to changes and can be easily modified unintentionally, which may lead to inconsistencies in the model.

The blue color helps users quickly identify sketches that require additional constraints or dimensions to ensure that they behave as intended. This is crucial for maintaining the integrity and reliability of the CAD model during later modifications or when generating 3D features from the sketch. By understanding that blue represents under-defined geometry, users can better manage their sketches and ensure they are fully defined, helping to mitigate any potential errors later in the design process.