Functions & Services of an OS

2. 2. Graphical user interface (GUI): Allows a user to interact with visual objects on a device's monitor via gestures, such as clicking, swiping, dragging & dropping, etc.
      • Fosters the use of terms like icons, folders, buttons, ribbons, windows, etc.
      • Each icon or button represents a file, folder, executable (binary file), link, or disk.
      • Clicking, or using other gestures, on an icon or button would either access the underlying item or perform an action upon it.
      • GUI is more convenient for use on touch devices than a command-line interface.
   3. Batch systems: Represents a method in which a collection of tasks, called jobs, are executed in groups (recall the batch OS type.)
      • A user would interact with such a system by either supplying punch cards or describing what jobs to perform using a job-control language.
      • Batch systems are used today on specific-purpose machines, like bank or payroll systems.