Convention over configuration is a simple concept. Systems, libraries, and frameworks should assume reasonable defaults without requiring that unnecessary configuration systems should “just work.” Popular frameworks such as Ruby on Rails and EJB3 have started to adhere to these principles in reaction to the configuration complexity of frameworks such as the initial Enterprise JavaBeans? (EJB) specifications. An illustration of convention over configuration is something like EJB3 persistence. All you need to do to make a particular bean persistent is to annotate that class with @Entity. The framework will then assume table names and column names from the name of the class and the names of the properties. Hooks are provided for you to override these names if the need arises, but, in most cases, you will find that using the frameworksupplied defaults results in a faster project execution.