" promotion model— promotes a product or service role model — person who acts as a behavioural or moral example to others. Models as physical objects physical model — physical representation of an object; in engineering, similitude is used in the scientific testing of physical models . scale model — a replica or prototype of an object built as a hobby or for research. a particular version of a series of vehicles produced by an automobile manufacturer is known as a model. Model-View-Controller (MVC) is a software architecture that separates an application's data model, user interface, and control logic into three distinct components so that modifications to one component can be made with minimal impact to the others. MVC is often thought of as a software design pattern. However, MVC encompasses more of the architecture of an application than is typical for a design pattern. Boat Building Model Sail Hence the term architectural pattern may be useful (Buschmann, et al 1996), or perhaps an aggregate design pattern. Operation In broad terms, constructing an application using an MVC architecture involves defining three classes of modules. "

" Developed between 1970 and 1973, it is a quantum field theory, and consistent with both quantum mechanics and special relativity. To date, almost all experimental tests of the three forces described by the Standard Model have agreed with its predictions. However, the Standard Model is not a complete theory of fundamental interactions, primarily because it does not describe gravity. The Standard Model The Standard Model contains both fermionic and bosonic fundamental particles. Fermions are particles which possess half-integer spin and obey the Pauli exclusion principle, which states that no fermions can share the same quantum state. Bosons possess integer spin and do not obey the Pauli exclusion principle. Informally speaking, fermions are particles of matter and bosons are particles that transmit forces. Boat Controlled Model Radio Sail For a detailed description of the differences between fermions and bosons, see the article on identical particles. In the Standard Model, the theory of the electroweak interaction (which describes the weak and electromagnetic interactions) is combined with the theory of quantum chromodynamics. "