Which of the following is NOT a device used to manage time?

A directory is considered a tool for storing and organizing information, such as contact details or resources, rather than a device designed specifically for time management. In contrast, a day planner, to-do list, and pocket calendar are all focused on helping individuals manage their schedules, prioritize tasks, and keep track of appointments and deadlines. These tools support effective time management by allowing users to allocate their time more efficiently and ensure they are aware of their responsibilities and commitments. Thus, identifying a directory as not being a time management tool aligns with the understanding of how these devices serve different functions in personal and professional organization.