| ADFS | Advanced Disc Filing System |
| Adjust button | Used mainly for adjusting selections, but often for modified versions of the select button equivalent. |
| Application Directory | Special case of a RISC OS directory which always has a name beginning with a "!" |
| CDFS | Compact Disc Filing System |
| Desktop | The RISC OS GUI |
| Draw | Standard vector based drawing application supplied with RISC OS. |
| Dynamic Areas | Areas of memory which can be used easily for dynamic memory requirements of an application. |
| Easter Egg | Hidden feature within the operating system - usually of no productive use. |
| Filer | RISC OS Interface to a filing system, allows access to and control of the media |
| Filer Window | A Window which displays the contents of a directory folder on a filing system |
| Font Cache | Area of memory used for storing font data to speed up reconstruction of on screen fonts. If you have plenty of memory you should configure a decent sized Font Cache. |
| GUI | Graphical User Interface (Windows, menus and mice) |
| Iconbar | Grey bar at the bottom of the RISC OS Desktop |
| Menu button | Middle mouse button, usually results in a menu at the pointer when clicked. |
| Module | Relocatable modules provide extensions to the OS kernel or applications which multi-task even outside the Desktop environment and provide service calls for other applications to make use of. |
| Paint | Standard pixel based application supplied with RISC OS for editing of Sprite files. |
| Pinboard | Background area of the Desktop above the Iconbar, where you can Pin files and directories for easy access. Pinboard can have a picture rather than plain or graduated backdrop and the picture can be scaled or tiled to suite needs. |
| Pixel | A single dot on the display screen or a televison set. |
| RAM Disc | Area of memory which has been reserved as a temporary filing system. Once configured can be treated just like a disc, but will loose its contents when the system is rebooted or switched off. |
| RMA | Relocatable Module Area - Area of memory which the operating system uses for managing Relocatable modules. |
| Select button | Left mouse button, used for selecting items. |
| Sprite | Pixel based file format for storing pictures such as Desktop Icons or Photographs. |
| Sprite Pool | Special area of memory which holds all the loaded icon sprites for use within the RISC OS Desktop. |
| System Modules | Module files which were supplied as part RISC OS or as updates to extend functionality of the system. These are located within !Boot.Resources.!System |
| WIMP | Accronym for Windows Icons Menus and Pointers, otherwise known as the Window Manager |
| Window Manager | The main system component of the RISC OS Desktop that manages applications use of Windows, Menus and interaction via the Mouse |