Generally speaking, a wiki is a website that allows logged in users to work together on mainly textual webpages, creating links to new pages, revising existing content, reverting back to previously added content and so on.
According to Wikipedia , the word wiki means fast in Hawaian named by the creator of the first wiki, Ward Cunningham. The following YouTube video is an easy and fun way to understand what a wiki can do in general:
Are we ready for handing over ownership?
In their exploration of wikis, Dalke et al (2004) noticed:
"It was particularly difficult to get the teachers to take advantage of the collaborative properties of the wiki philosophy. For example, on the second afternoon of project work, the teachers' assignment was to go onto each other's wiki pages and make suggestions for changes. But-- with various degrees of politeness -- the participants refused to alter one another's work. Many of them were plainly uncomfortable doing so" (p.21)
Sometimes students do not feel comfortable handing over ownership that easily. Especially students, who are not confident about their academic writing skills, may feel intimidated to submit their work for others to modify.
In order to avoid difficult situations you could start by asking students to edit an anonymous text or create a series of pages from scratch.
Dalke, A., Cassidy, K., Grobstein, P. Blank, D. (2007) Emergent Pedagogy: Learning to Enjoy the Uncontrollable and Make it Productive in Journal of Educational Change, v.v8, i.2, pp. 111-130.