## 3 Materials and Methods
### Planning Phase
#### 3.1.1 Rationale for this Literature Review  
Due to the current coronavirus crisis situation in all levels of education and because of the rapid migration to various virtual and/or distant modes of education, many research initiatives appeared to search exactly that. Thus, the effectiveness of SVREs in open and distance learning in the year 2020 (and most probably in the year 2021) in all levels of education seems to be investigated a lot worldwide and has become a current popular research and development topic. It has been supported that in education, things that were in the agenda to be done within 20 years, were planned, designed, implemented, and realized--willingly or not--within two weeks. Admittedly, the year 2020, affected by COVID-19, was a transitional stage for e-learning and distance education, globally. Having said that and experienced these transitional events, the researchers and authors of this paper evidenced an increase in the transformation of e-learning with or without SVREs and with or without deep and meaningful learning (DML). Presumably, this has been recognized as the (harsh) reality of learning during the continuous COVID-19 pandemic situation worldwide. Our literature review, however, covers the period from the beginning of the Second Life (2003-2004) platform's adoption in e-learning to 2019; this is the pre-coronavirus time. Furthermore, the review only considers e-learning in higher education. In addition, the literature review we carried out is not limited only to Second Life in education, as in some previous reviews [31; 34]. Other existing virtual worlds designed and realized for learning also fall within our research interest. Such virtual learning worlds are, for example, Open Simulator, Active Worlds, and others. The authors believe that this research study will eventually be useful for comparing the two states of past and present/future e-learning. It could also be a reference point for comparing and contrasting the previous socio-technical advances and pedagogic effectiveness of SVREs (before 2020) to the enforced, recent advances that had to be urgently adopted for the needs of remote learning and its overall effectiveness. The related research studies and research reports that appeared during 2020, that is, after our literature review was carried out, are 4 in number [47; 48; 49; 50] and they do not holistically examine the combined issues (cognitive, social, and affective) that we emphasize in this study. The main research objective of this study was to address specific gaps and under-researched issues in the research literature and assess the potential of SVREs by mapping their use to the requirements of deep and meaningful e-learning (DML). Currently, there is a social learning need and socio-economic pressure for preparing the future human workforce for the post-coronavirus era. Predicting and re-assessing the readiness of HE institutions for this task through the evaluation of outcome-based research has been a motivational force for this study. In so proceeding, the focus has been on the learning experiences, the potential, and the conditions for the achievement of DML, considering and integrating all the affective, cognitive, and social domains. Concurrently, the focus has also been on the rapid changes and enforced technologies in open and distance modes of higher (and not only) education while also having socio-technical factors and virtual reality technologies advancements in mind. Apart from monitoring the changes in the transitional periods before and after 2020, the outcomes of this study are intended to assist educators and practitioners in the collaborative design and implementation of high-quality distance learning programs utilizing SVREs and/or other related information and communication technologies.