A component grade extends on the notion of component defaults (fluid.defaults). Where a fluid.defaults is used to store and retrieve a component's default settings, the grade is a form of type definition that represents a collection of component defaults and is intended for reuse in other component's defaults definition. In other words, a particular component's fluid.defaults can be called a grade when the component name is used as a base grade within another component's defaults.
Grades essentially Developers can create their own fluid.defaults / grades as well as use them to build upon each other, and can be composed as neededcompose them as needed.
Infusion Framework already contains several predefined component grades that are intended to be used (but do not have to be) as the initial building blocks for the external components and grades. The following table describes the exiting grades offered by the Framework these grades and how they relate to each other.Component developers are free to define their own grades that may (or may not) be built upon any of these grades.
A "little" component is the most basic component: it supports options merging with defaults (Little Components).
A "model" component is already a little component that additionally provides supports for any model defined a component's model, defined in the components options, and operations on it (Model Components).
An "evented" component is already a little component that additionally instantiates event firers based on default framework events (onCreate, onDestroy, onDetach) and events declared in the options (Evented Components).
A "view" component is already an evented and a model component that is DOM aware and supports a view (View Components).
A "renderer" component is already a vew component that bears a renderer. There are additional features provided by this component type grade specified on the Useful functions and events section of the Renderer Components page