" For example, an operating system command to display the current time. It displays the time and is done; it does not wait for events . For more information, see: Event-driven_programming Implementations The pattern was first described in 1979 by Trygve Reenskaug, then working on Smalltalk at Xerox research labs. This original implementation inspired many other GUI frameworks such as: The NeXTSTEP and OPENSTEP development environments encourage the use of MVC. Cocoa, based on these technologies, also uses MVC. Microsoft Foundation Classes (MFC). The Java Swing GUI library. Hot Import Tuner Model More recently there have been attempts to apply MVC architectures for web-based interfaces. In the design of web applications, MVC is also known as a "Model 2" architecture in Sun parlance. "

" The first experimental deviation from the Standard Model came in 1998, when Super-Kamiokande published results indicating neutrino oscillation. This implied the existence of non-zero neutrino masses since massless particles travel at the speed of light and so do not experience the passage of time. The Standard Model did not accommodate massive neutrinos, because it assumed the existence of only "left-handed" neutrinos, which have spin aligned counter-clockwise to their axis of motion. If neutrinos have non-zero mass, they necessarily travel slower than the speed of light. Therefore, it would be possible to "overtake" a neutrino, choosing a reference frame in which its direction of motion is reversed without affecting its spin (making it right-handed). Since then, physicists have revised the Standard Model to allow neutrinos to have mass, which make up additional free parameters beyond the initial 19. A further extension of the Standard Model can be found in the theory of supersymmetry, which proposes a massive supersymmetric "partner" for every particle in the conventional Standard Model. Mountain Model Import Supersymmetric particles have been suggested as a candidate for explaining dark matter. Although supersymmetric particles have not been observed experimentally to date, the theory is one of the most popular avenues of research in theoretical particle physics. "