According to the Virginia Polytechnic Institute and State University, computers do very well in "number crunching." An example given is sorting a random collection of a million numbers and putting them in order, which a computer can do in seconds. A human mind would take years to complete the exact same operation. A practical use would be to sort Social Security numbers for the Social Security Administration. Every time a new person applies, a unique number has to be generated, and a central computer looks at all the millions of numbers already in existence. It generates a new number so no duplication occurs.
In "the old days" before computers, an engineer or draftsman had to sit at a drafting table to design a part. In 2011, a designer uses a mouse to draw lines on a computer screen. The drawings can be shaded in or colored as desired. Learning how to use a computer-aided design, or CAD program, usually requires a formal education.
Computers today control robots and machines to manufacture parts. Before computers became widespread, parts were manufactured by hand, or by a human operator controlling machines. In computer-aided manufacturing, a part is drawn up on a computer screen. The engineer hits the "Send" button, and the computer guides a mill in creating the part. What once took days can be completed in less than an hour. The process of going right from the drafting screen to manufacturing is called CAD/CAM, which stands for Computer-Aided Design/Computer-Aided Manufacturing.
Computers can take a series of two or more pictures and combine them to form a three-dimensional image. This picture can be rotated by the movement of a cursor or mouse. A common use is medical imaging, where a medical scan develops a series of two-dimensional images. The computer combines them and forms a three-dimensional image of an internal organ.
Computers are approaching the ability to make complex decisions. While not as powerful as the human mind, they can analyze complex data and develop solutions to problems. According to Professor John McCarthy of Stanford University, a common use of artificial intelligence, or AI, is computerized chess games. The AI program analyzes all the possibilities, then chooses the best move.