A multiuser system is a type of computer system that allows multiple users to access and use the resources simultaneously. This setup enables users to share hardware, software, and data, making it efficient for collaborative work. Examples of multiuser systems include mainframes and servers, which can support many users at once. In a multiuser environment, each user typically has their own account and permissions, ensuring security and privacy. Operating systems like Unix and Linux are designed to manage these user accounts effectively, allowing for resource allocation and task management without conflicts.