Instructional technology is the theory and practice of design, development, utilization, management, and evaluation of processes and resources for learning (Seels & Richey, 1994).

The latest AECT's definition is "Educational technology is the study and ethical practice of facilitating learning and improving performance by creating, using and managing appropriate technological processes and resources"(Richey, R. C., Silber, K. H., & Ely, D. P. 2008).

It is a specific technology field that deals with creating resources for learning. My definition is that instructional technology is the field of systematically developing the research and practical learning of education using technology . It applies a variety of technology so that learners can learn more effectively.

Behaviorism is the main cause of human behavior. It uses the principles of stimulation and reaction, not voluntary learning processes. Learners are passive beings in behaviorism and learning is the change in behavior produced by the results of experience or practice. The theory is that a person's character is influenced by genetics, but is shaped by experience and environment, and acts on the basis of it. It also emphasizes that behaviorism can be rewarded and punished based on changed behavior.

The key concept of cognitivism is that it looks mind as a "Black Box". Cognitivism focuses on inner mental activities such as thinking, knowing, memory. The fundamental concept of cognitivism involves how we receive, organize, store and retrieve the knowledge. The learner is viewed as an information processor and active beings in cognitivism. The learner actively accepts new information and actively organizes knowledge in conjunction with prior knowledge.

Constructivism states that learning is an active, contextualized process of constructing knowledge rather than acquiring it. Knowledge is constructed based on personal experiences and hypotheses of the environment (Ertmer, P. A., & Newby, T. J. 1993). Constructivism is the process of building meaning through personal subjective experiences and interactions. The constructivism learning theory places the subject of learning on the learner and gives the learner the ability to actively construct the appropriate knowledge. Therefore, learning is a process in which individuals construct their own meanings, so the center of learning becomes the learner, not the instructor.