How GIS and CAD Interrelated ?

Computer aided design (CAD) is the use of computer technology for the design of objects, real or virtual. CAD often involves more than just shapes. GIS and CAD are interrelated, an eg is Carrying GIS Data in AutoCAD .As in the manual drafting of technical and engineering drawings, the output of CAD often must convey also symbolic information such as materials, processes, dimensions, and tolerances, according to application-specific conventions.CAD is extensively used in many applications such as automotive, shipbuilding, and aerospace industries, industrial and architectural design, prosthetics, and many more. Now CAD is also widely used to produce computer animation for special effects in movies, advertising and technical manuals.CAD also very helpful for research in computational geometry, computer graphics (both hardware and software), and discrete differential geometry.
Some of the GIS services and CAD conversions offered in CAD are as follows:

CAD DRAFTING and CAD CONVERSION SERVICES
• Autocad drafting
• Engineering /Mechanical services
• Scan to cad conversion
• AutoCAD coversion to drawings
• Confidential cad conversion
• DGN conversion
• Multilayer Cad conversion
• AutoCAD digitization
• CAD to GIS
• GIS to CAD
• Paper to CAD