CAD (computer aided design) is using a computer program to draw accurate drawings of components and systems. Software used in schools is Techsoft 2D Design and ProDesktop. In industry a wider range of software is used which is often complicated but is more powerful enabling engineers and designers to produce any design for manufacture e.g. Autocad, Ideas, ProEngineer.
CAM (computer aided manufacture) machines controlled by computer are able to manufacture components and whole products. In schools CNC lathes and mills are fairly common, Laser cutting machines are becoming popular, 3D and 4D routing machines are also to be found. Engraving machines have also been developed to enable cost effective 3D work to be machined. Rapid Prototyping machines are also becoming more affordable - these machines can produce 3D products directly from a 3D drawing such as those produced by Prodesktop. Robots can be included in this category and complete many tasks in manufacturing which would have been done by people.
Advantages of using CAD systems to produce drawings include greater accuracy even when zoomed in, corrections and modifications can be done on screen, drawings are in a digital form and can be shared across networks and the INTERNET, also every copy is as good as the original, the output can be linked to a CAM machine (i.e.CAD/CAM) and the product manufactured directly. Disadvantages include the cost of the software, the training costs and the time taken to train the engineers and designers, theft of digital images is possible without detection and the copies are of course as good as the original, the cost of the workstations and their maintenance is high.
Advantages of CAD include the high level of accuracy and repeatability of the components, the machines can be managed by semi-skilled workers, some shapes could not be produced easily on manual machines (In fact with RP machines shapes can be produced which could not be machined by hand). Disadvantages include the cost of the machines, their maintenance, the training needed for the operatives, the high cost of the software, the loss of skilled workers (many traditional skills are no longer needed).
The future will be one where CADCAM machines will become more advanced and cheaper and of course new technologies will emerge - Replicators seen in science fiction shows such as Star Trek may become reality.