All house design software uses CAD technology. CAD stands for Computer Aided Design and represents a type of software package that aids in the drafting of of objects including houses. This drafting can either be done in 2D or 3D. The most modern CAD packages allow you to rotate the objects so that you can see them from different angles. CAD is particularly effective when used in the design and drafting of houses. Sometimes you may notice an extra D on the end of CAD - CADD.. This is not a spelling mistake. CADD software programs are another branch of CAD, where CADD programs allow you complex mathematical modeling. CADD stands for Computer Aided Design and Drafting.