What is Nucleus in ATG? Nucleus is is ATG Commerce Component Model that helps to assemble application components using configuration file. A configuration file specifies the name of components and required parameters by components Nucleus doesn't provide any application-specific functionality Application functionality is provided by JavaBean Components Nucleus helps to create components and helps to find components each other To do this, nucleus organizes application components into a hierarchy, and assigns a name to each component, based on its position in the hierarchy For example, a component named /services/logs/FileLogger represents a component called FileLogger , contained by the container component called logs , which is itself contained bcalled services . The services component is contained by the root component of the hierarchy, which is Nucleus. Components in the hierarchy can refer to each other by name ...