Belonging is a powerful, fundamental, and pervasive human need based on strong biological and psychological mechanisms (Deci & Ryan, 2000; Patrick, Knee, Canevello & Lonsbary, 2007). The importance of feeling connected to others can be placed only behind safety needs and basic physiological needs (Maslow, 1968). Extensive evidence underlines the importance of belonging for human well-being, physical health, and mental health (for an overview see Baumeister & Leary, 1995). Mediated communication through telephone, text messaging, email, instant messaging, and online communities has broadened our communication horizon significantly. Communication technology affords social interaction and awareness of people's situation, activities, and well-being over geographical distance and time. This allows us to fulfill our pervasive and fundamental social needs in the face of our changing lifestyles, including families dispersing over larger areas, elderly living alone, and increased business travel. At the same time, however, doubts remain as to whether mediated communication can afford the same affective characteristics as face-to-face interaction, which is often considered the gold standard of communication. Some research has been done in this area. For example, Shklovski, Kraut & Cummings (2008) have shown that mediated communication helps maintain feelings of closeness after a residential move.

In this context of mediated communication the concept of connectednes has been introduced. The concept of connectedness has been characterized as a sense of keeping up-to-date, being involved, being in touch or sharing with others within ongoing social relationships, or a sense of having company (IJsselsteijn, Van Baren, &Van Lanen, 2003; Markopoulos, Romero, Van Baren, IJsselsteijn, De Ruyter, & Farshchian, 2004; Romero Herrera, Markopoulos, Van Baren, De Ruyter, IJsselsteijn & Farshchian, 2007). However, the exact nature of this key outcome of mediated communication has hitherto remained relatively unexplored. Up to now most research and design of communication technology has largely been based on an intuitive sense of what the feeling of connectedness is. Social presence has been more commonly discussed in literature on mediated communication applications (Biocca, Harms & Burgoon, 2003). Social presence differs markedly from connectedness: whereas social presence is primarily a direct perceptual experience during contacts, connectedness is a more lingering feeling of belonging. Being a vital consequence of mediated communication, more fundamental insight in the feeling of connectedness is needed. To achieve this, we collected and used relevant knowledge from the fields of social psychology, media psychology, and HCI to establish the concept of social connectedness. The concept of social connectedness is timely and necessary in order to theoretically anchor and embed belongingness in the context of both mediated and unmediated communication.

Based on an extensive literature review, we propose an inclusive definition of social connectedness, which incorporates all key aspects of belonging. We define social connectedness as the ongoing momentary affective experience of belonging based on awareness and appraisals of social relationships and interactions. Social awareness holds two components: (1) the sense of being in touch, and (2) the sense of involvement and sharing. The social appraisals may be both quantitative and qualitative in nature. The quantitative appraisals pertain to the perceived size of one's social network and the amount (frequency and duration) of social interaction with social network members. The qualitative appraisals focus on the closeness people experience in their social relationships and interactions. Thus, the feeling of being in touch and involved with others, a sense of having a sufficiently large circle of friends, having a satisfactory amount of social interaction, and the level of closeness in one's social life can each contribute to social connectedness.

Social connectedness, as we define it, is not fully captured by any single existing concept. Two specific aspects render the concept unique: (1) the incorporation of the new concept of social awareness and (2) its temporal frame. Long-term social appraisals contribute to social connectedness, given that most people’s social networks and relationships tend to be stable. However, social connectedness is conceptualized as an ongoing momentary experience, emphasizing also the short-term social information originating from recent interactions and awareness information. Thus, in contrast to already existing concepts, such as loneliness and closeness, social connectedness is potentially more sensitive to small fluctuations induced by mediated and unmediated communication, due to the use of a relatively short-term scope. Social connectedness is therefore more sensitive to changes over time than other concepts related to belonging. In conclusion, the concept of social connectedness allows for precise operationalization, measurement, and systematic empirical study of mediated and unmediated communication. Social connectedness is thus uniquely geared to understanding and establishing how various communication modes may foster a sense of belonging.