Instructional Design is the practice of maximizing the effectiveness, efficiency and appeal of instruction and other learning experiences.
Instructional Design as a Process:
Instructional Design is the systematic development of instructional specifications using learning and instructional theory to ensure the quality of instruction. It is the entire process of analyzing learning needs and goals and the development of a delivery system to meet those needs.
Instructional Design as a Discipline:
Instructional Design is a branch of knowledge concerned with research and theory about instructional strategies and the process for developing and implementing those strategies.
Instructional Design as Reality:
Instructional design can be started at any stage in the design process. Often a outline of an idea is developed to give the foundation of an instruction-situation. By the time the entire process is done the designer reviews back and checks to see that all parts of the “science” have been taken into consideration. Then the entire process is documented as if it occurred in a systematic fashion.