Diffusion control refers to the process of managing and regulating the spread or movement of something, such as information, ideas, or substances, from one place to another. This can be achieved through various means, such as barriers, filters, or restrictions, in order to control the rate or direction of diffusion. In other words, diffusion control is the deliberate effort to influence the diffusion of something in order to achieve a desired outcome. This term is commonly used in fields such as science, technology, and marketing, where the effective management of diffusion can greatly impact the success of a product, idea, or innovation.