Aspect ratio : Ratio of display width to height.
Block: Grouping one ore more objects combined to form a single object. On creation, blocks are given a name and an insertion point.
CAD: Computer-aided design or computer aided drafting. Also CADD, for computer aided drafting.
Command line: Text area reserved for keybord input, messages, and prompts.
Coordinates: X, y and z location relevant to a model’s origin (0,0,0).
Crosshairs: Type of cursor.
Drawing file: Electronic representation of building or object.
Cursor: Active object on a video display that enables the user to place graphic information or text.
Drawing web format (DWF): Compressed file format that is created from a DWG file, ideal for publishing and viewing on the web.
DWG: File format for saving vector graphics from within AutoCAD.
Drawing interchange format (DXF): ASCII or binary file format of an AutoCAD drawing, for exporting AutoCAD drawings to other applicatioins or importing those from other applications into AutoCAD.
Entity: Geometric element or piece of data in a CAD drawing, such as a line, a point, a circle, a polyline, a symbol, or a piece of text.
Explode: Disassemble complex object such as blocks and polylines.
External reference: File or drawing that is used as background in another drawing but can not be edited, except in its original drawing. Examples include building grids and site information. Also called X-Ref.
Layer: Entity used for classification in a CAD drawing, whose properties allow for manipulation and flexibility of information in the drawing.
Model: In AutoCAD, a two- or three dimensional representation of an object; or a three dimensional replica of a design, whether physical or digital.
Model space: One of two primary spaces in which AutoCAD entities exist. Model space is a three-dimensional coordinate space in which both two dimensional and three-dimensional drafting and design are done at full (1:1) scale.
Paper space: Other primary AutoCAD space. Used for creating a finished printable or plottable layout; usually contains a title block.
Polyline: Object made up of one or more connected segments or arcs, treated as a single object.
Sheet file: Print or plot-ready electronic representation of a presentation sheet, containing a view or views of the model, text, symbols, and a title block.
User coordinate system (UCS): System that defines the orientation of x, y, and z in three-dimensional space.
UCS icons: Keys that indicate the direction of x, y, and z planes, as well as whether the user is in paper or model space.
Viewport: Bounded area that displays some portion of the model space of a drawing.
Window: Drawing area, including the command line and surrounding menus.