Editing Solid modeling (section)

===Parametric and feature-based modeling===
Features are defined to be parametric shapes associated with ''attributes'' such as intrinsic geometric parameters (length, width, depth etc.), position and orientation, [[geometric tolerance]]s, [[material properties]], and references to other features.<ref name = "Features">{{cite journal |title= Challenges in feature based manufacturing research |journal= Communications of the ACM |volume= 39 |issue= 2 |pages= 77–85 |author=  Mantyla, M., Nau, D., and Shah, J.|year= 1996|doi= 10.1145/230798.230808 |s2cid= 3340804 |doi-access= free }}</ref> Features also provide access to related production processes and resource models. Thus, features have a semantically higher level than primitive closed regular sets. Features are generally expected to form a basis for linking CAD with downstream manufacturing applications, and also for organizing [[database]]s for design data reuse.  Parametric feature based modeling is frequently combined with constructive binary solid geometry (CSG) to fully describe systems of complex objects in engineering.