An adaptive system is a system that is able to adapt its behavior according to changes in its environment or in parts of the system itself. A human being, for instance, is certainly an adaptive system; so are organizations and families. Some man-made systems can be made adaptive as well; for instance, control systems utilize feedback loops in order to sense conditions in their environment and adapt accordingly. Robots incorporate many of these control systems.
Diffusion of innovations theory can help to explain the uptake of new ideas, practices and products by individuals and social groups -- human adaptive systems.