A screw thread, often shortened to thread, is a helical structure used to convert between rotational and linear movement or force. A screw thread is a ridge wrapped around a cylinder or cone in the form of a helix, with the former being called a straight thread and the latter called a tapered thread.
The history of the single-lens reflex camera (SLR) begins with the use of a reflex mirror in a camera obscura described in 1676, but it took a long time for the design to succeed for photographic cameras: the first patent was granted in 1861, and the first cameras were produced in 1884 but while elegantly simple in concept, they were very complex in practice.
The Gateway to Up-To-Date Information on Integrated 'Whole Building' Design Techniques and Technologies. The goal of 'Whole Building' Design is to create a successful high-performance building by applying an integrated design and team approach to the project during the planning and programming phases.