This, the 36th issue of the Transactions on Computational Science, is devoted to the area of Cyberworlds and Cybersecurity. The first four papers constitute extended versions of selected papers presented at the 2018 International Conference on Cyberworlds, CW 2018. A further two papers were accepted following an open Call for Papers and cover the areas of fast 3D segmentation using geometric surface features and nature-inspired optimization for face recognition.