This book presents the results of the research in one of the most complex and difficult areas of research such as research in the areas of thinking and understanding. This research that is carried out in the newly founded Queen Jadwiga Research Institute of Understanding www. qjfpl. org/QJRIU/ Eng/Eng QJRIU PO O. htm is focused on research on the problem of visual – –– understanding and visual thinking. Visual understanding is part of the general understanding problem and it is not possible to carry out the research in visual understanding without reference to the nonvisual understanding problems. Understanding appears as the result of the thinking processes, and doing research in the area of understanding there is a need to include thinking process as one of the research problems that should be solved in the context of und- standing investigations. According to our knowledge, this book is the first attempt to investigate the complexity of the visual thinking problems in the context of building the thinking machine. The aim of our research is to build the machine that can have capabilities to solve visual problems during thi- ing process. We are aware how complex this problem is and we are aware that the results of our research are only the first steps in building the thinking machine being able to solve complex visual problems.