The purpose of this paper is to present selected literature on learners and collaborative learning in virtual worlds. Research in virtual worlds on collaborative learners is gradually emerging and will gain in significance, particularly in online and distance education environments. It will be argued that the design and functionality of virtual worlds provides a platform for collaboration, particularly for learners that have grown up with digitalized learning environments and may have developed a preference for them. The paper starts with a clarification of terms, a description of the various categories and a chronological overview of the emergence and development of these environments. The familiarisation with the subject matter continues through a discussion of the significance, opportunities and barriers that this medium offers and is followed by an examination of learners' characteristics and their implications for teaching and learning in virtual worlds. Drawing on recent examples of virtual worlds in education and some current statistics, the paper strives to meet the continuing education needs of practitioners and educator using virtual worlds. It concludes with an examination of the challenges and perspectives on collaborative learning in these environments and the trends in virtual worlds that impact the delivery of student learning.