Windows Managers

• Windows managers are programs whose only purpose is to open windows, be they folders or applications. They do not provide any additional functionality beyond creating windows for these folders and applications.
  
  

Desktop Environments

• Desktop environments are full-featured, integrated, graphical computing environments. In addition to creating windows, they often feature graphical components for system tasks. For example, they can provide a trash bin for deleting files, menus for accessing system components and applications, and task bars for displaying system information.
  
  

Desktops vs. Windows Managers

• A desktop provides a framework for developers to make programs within the environment. Users can choose to use a particular windows manager within a desktop environment, or to use no desktop environment at all. In this case, users can include the features of desktops in their computing environment by installing and running programs for each desired feature.
  
  

Examples

• Microsoft's Windows operating system is an example of a full desktop environment. UNIX and Linux operating systems, on the other hand, usually use separate, distinct windows managers and desktops.