1 Activate Your Free Trial!  Yawl. Yawl, two-masted sailboat, usually rigged with one or more jibsails, a mainsail, and a mizzen. In common with the ketch, the forward (main) mast is higher than the mizzenmast, but the mizzenmast of a yawl is placed astern of the rudder post, while that of the ketch is closer amidships.
System design is documented in the System Design Document (SDD). It describes design goals set by the project, subsystem decomposition (with UML class diagrams), hardware/software mapping (with UML deployment diagrams), data management, access control, control flow mechanisms, and boundary conditions.
All of these approaches to system design omit the most important part of the process â the end user. User-Centered Design (UCD) is the process of designing a tool, such as a websiteâs or applicationâs user interface, from the perspective of how it will be understood and used by a human user.