Instructional theories are important in instructional materials design. Martin Nystrand argues that teachers rarely choose classroom discussion as an instructional format. Lukather periodically contributes material and expertise to instructional and educational enterprises. Learning theories also play an important role in the design of instructional materials. These theories of learning play a role in influencing instructional design. This teaching model is contrary to many modern instructional models. They found that the format of instructional materials either promoted or limited learning. It includes coursework tools intended for use by researchers, instructional designers, instructors, and students. Informal learning became an area of growing importance in instructional design, particularly in the workplace. Informational/instructional fear acquisition is learning to fear something by getting information. The U.S. and Canadian governments also used animation for training and instructional purposes. In education, blogs can be used as instructional resources. Leinhardt (1990&colon; 3-4) distinguished between two types of teaching related to explanations&colon; instructional and disciplinary. It provides human and material resources for instructional and broadcast purposes. She taught herself to play by watching instructional DVDs.