KDE offers users many features such as drag and drop, session management, internationalization, and network transparency, but application developers are the ones who must implement them. The KDE/Qt libraries make this task easier by performing common application functions. Configuration files are accessed with the class KConfig; session management is handled in most cases by KTMainWindow; application resources can be located with KStandardDirs and are usually manipulated with KDE/Qt classes, such as QPixmap or KAudioPlayer; files can be loaded or saved locally or remotely using KIO_NetAccess.