When a learner uses a computer application as a mindtool, it means that the learner is using that software program to engage in constructive, higher order, critical thinking. The concept was developed by David Jonassen, who was a professor of learning technologies and educational psychology at the University of Missouri until his death in 2012. The focus of his professional life was on problem solving, and his mindtools concept was particularly influential. His first book on the concept was Computers in the Classroom: Mindtools for Critical Thinking, published in 1995. This entry details the concept of mindtools and discusses its impact.