Explicit instruction occurs in an instructional task that provides the learner with specific information or directions about what is to be learned from the task. Explicit instruction often comes in the form of rules or verbal statements that provide guidance to the student about what is to be learned. Although explicit instruction contrasts with implicit instruction, instructional tasks are often graded with elements of each. Thus instruction can be relatively explicit or relatively implicit. Explicit instruction works through feature focusing, drawing the learner's attention to the valid or critical features (feature validity) of the content to be learned. Implicit learning can be designed to promote feature focusing, as well, although often it does not.