A point of consensus among many DE researchers and practitioners is that interaction is a crucial element for learning; and thus, for effective online education (Bannan-Ritland, 2002; Gunawardena & McIsaac, 2004; Moore, 1993). Interaction among students enhances the learning experience and increases students’ satisfaction with the course (Bull, Kimball, & Stansberry, 1998; Palloff & Pratt, 1999). Furthermore, interaction among learners and instructors increases learners’ positive attitudes toward and motivation to learn (Fulford & Zhang, 1993; Ritchie & Newby, 1989). In one of the few theories native to distance education, Moore (1993) explained how interaction and structure are critical to success in online education.

In his model of transactional distance (TD), Moore contended that DE is “the mutual action between teachers and students, in environments whose uniqueness is separation from each other, and as a result exhibit unique behavior patterns of distance education” (Moore & Kearsley, 2005, p. 224). The physical distance in DE, not present in traditional education, results in a communication and a psychological gap with the potential for disrupted communication and misunderstanding among learners and the educator. Dialogue and course structure, both adaptable to learner needs, are two of the variables that decrease TD and increase learning effectiveness (Moore, 1993).

Effective teaching and learning at a distance depends upon the nature of an interaction and how interaction is facilitated through a technological medium (Moore & Kearsley, 2005). Moore (1989, 1993) noted three types of unidirectional and bi-directional interactions necessary for effective online education:

• Learner-content interaction is considered a distinguishing strength of all DE and refers to students’ intellectual interactions with content that result in changes in understanding, perceptions, and cognitive structures. When a student reads a text and engages in an internal dialogue about its content, a student practices guided didactic conversations or interaction with the content (Holmberg, 1983; Moore, 1989).

• Learner-learner interaction is a newer dimension of DE because earlier generations of DE did not readily support collaboration among peers (Garrison & Anderson, 203 Haythonthwaite, 2002; Taylor, 2001). It is both cognitive and social in nature and refers to communication between and among peers with or without the teacher present (Moore, 1989).

• Learner-teacher interaction, a factor that distinguishes online education from independent studies, refers to all communications between the teacher and the student that occurs throughout the course (Moore, 1989). It also refers to the organization that the educator provides to guide learning throughout the course (i.e. curriculum development) and the role that the educator plays in motivating and supporting students’ learning (Moore, 1989).

A lack of teacher-learner and learner-learner interaction is deemed problematic, and opportunities for high levels of teacher-learner, learner-learner, and learner-content interaction improve the learning process in DE (Baggerly, 2002; Moore, 1989).