Multiple document interface

A multiple document interface (MDI) is a graphical user interface in which multiple windows reside under a single parent window. Such systems often allow child windows to embed other windows inside them as well, creating complex nested hierarchies. This contrasts with single document interfaces (SDI) where all windows are independent of each other. A multiple document interface (MDI) is a graphical user interface in which multiple windows reside under a single parent window. Such systems often allow child windows to embed other windows inside them as well, creating complex nested hierarchies. This contrasts with single document interfaces (SDI) where all windows are independent of each other. In the usability community, there has been much debate about whether the multiple document or single document interface is preferable. Software companies have used both interfaces with mixed responses. For example, Microsoft changed its Office applications from SDI to MDI mode and then back to SDI, although the degree of implementation varies from one component to another. SDI can be more useful in cases where users switch more often between separate applications than among the windows of one application. MDI can be confusing if it has a lack of information about the currently opened windows. In MDI applications, the application developer must provide a way to switch between documents or view a list of open windows, and the user might have to use an application-specific menu ('window list' or something similar) to switch between open documents. This is different from SDI applications where the window manager's task bar or task manager displays the currently opened windows. In recent years it has become increasingly common for MDI applications to use 'tabs' to display the currently opened windows. An interface in which tabs are used to manage open documents is referred to as a 'tabbed document interface' (TDI). Another option is 'tiled' panes or windows, which make it easier to prevent content from overlapping.