A checklist is a list of tasks, questions, or points to consider in order to verify that important steps have been completed. There are three main types of checklists: procedural checklists that list steps in a required order, communication checklists that encourage organization, and project checklists that list tasks to complete. Checklists can be used for tasks, troubleshooting, coordination, discipline, and to-do lists. They are formatted with checkboxes and provide benefits like saving time and brainpower, enabling delegation, and helping users stay focused and organized.