CAD standards CAD standards CAD Standards are a set of guidelines for the way Computer-aided drafting (CAD), or (CADD) Computer Aided Design and Drawing, drawings should appear, to improve productivity and interchange of CAD documents between different offices and CAD programs, especially in architecture and engineering. Most common: Samples of standardised layers: Thickness for pens and plot: "0,13 mm Gray, 0,18 mm Red, 0,25 mm White, 0,35 mm Yellow, 0,50 mm Magenta, 0,70 mm Blue, 1,00 mm Green". In AutoCAD usually parts to be printed in black are drawn in 1 to 7 basic colors. Color layer: Green-Center, Magenta-Measure of length and
Computer-assisted proof the runtime environment and hardware. Other mathematicians believe that lengthy computer-assisted proofs should be regarded as "calculations", rather than "proofs": the proof algorithm itself should be proved valid, so that its use can then be regarded as a mere "verification". Arguments that computer-assisted proofs are subject to errors in their source programs, compilers, and hardware can be resolved by providing a formal proof of correctness for the computer program (an approach which was successfully applied to the four-color theorem in 2005) as well as replicating the result using different programming languages, different compilers, and different computer hardware. Another possible way