The Spring Framework's IoC container core is defined in two packages: org.springframework.beans and org.springframework.context. BeanFactory (org.springframework.beans.factory.BeanFactory) and ApplicationContext (org.springframework.context.ApplicationContext) are two important interfaces that provide a basis for IoC containers. BeanFactory provides the configuration framework and basic functionality and takes care of bean instantiation and wiring. ApplicationContext can also take care of bean instantiation and wiring