IOC term is coined by Martin Flower for describing a pattern where direct coupling between objects can be reduced by using service locator kind of architecture which is getting exploited in spring by what is called dependency Injection, which says that classes don't need to call another implementaion class and bind to that only rather container will injected dependent objects of declared interface resolved at startup or by lazy loading at request time.
Inversion of control is based on the phenomenon that says, when ever dependency betwen two classes (say class A and class B) now if A needs to access the methods of B, then following our traditional approach we go ahead and create and object of B in A, but as the fact of matter, B is there to serve A not A serving B creating objects for B , So in IOC the the the class B will try to inject its object into A rather than A creating object of B. so the control is reversed , during the run time now spring container takes care which class object to inject into other class.
Inversion of control or IOC is just a term. This term is used in spring framework for its dependency injection. Its all about this much , While your applications starts it will create the Objects of the Classes listed in application-servlet.xml file and serve that Objects to the classes which calling it through setter method, contructor,normal method. So that you don't need to create an Object of a class by yourself in that class.
Holywood principle "Don't call me , i will call you"
org.springframework.beans || ||--->|The BeanFactory interface advanced configuration mechanism capable of managing objects of any nature. || || org.springframework.beans.factory.BeanFactory || ||-->|BeanFactory is the actual representation of the Spring IoC container that is responsible for containing and otherwise managing bean
XmlBeanFactory implementation BeanFactory
XML configuration metadata +Business object =appplication (interdependencies between such objects)
