Provided are a system and/or method of providing a to-do list of a user. A device for providing a to-do list of a user may include: a communicator configured to communicate with an external device; a display; and a processor configured to determine at least one keyword used to determine at least one task to be performed by the user in the to-do list, based on data obtained by an application executed on the display, generate a keyword list of the determined at least one keyword, and display a graphical user interface (GUI) for selecting at least one of the at least one keyword in the keyword list by controlling the display.