Open textbooks are freely shareable and editable resources designed to operate in place of a specified textbook. As one approach to open educational resources (OER), they are not locked down by copyright restrictions but have an open licence that enables everyone to reuse, remix, revise, redistribute and retain them. Open textbooks can be used to challenge the relationship between students and knowledge. These books are adaptable – not fixed and static resources but dynamic ones. Students can edit and amend an open textbook as part of their study. This helps them to understand knowledge as an ongoing process in which they play an active role. These textbooks can be seen as part of a broader move towards ‘open pedagogy’, which emphasises open content and open practices.