C++ Programming. Program Design including Data Structures
Terms such as “the Internet,” which were unfamiliar just 25 years ago are now common. Students in elementary school regularly “surf” the Internet and use computers to design and implement their classroom projects. Many people use the Internet to look for information and to communicate with others.
The first device known to carry out calculations was the abacus. The abacus was invented in Asia but was used in ancient Babylon, China, and throughout Europe until the late middle ages. The abacus uses a system of sliding beads in a rack for addition and subtraction. In 1642, the French philosopher and mathematician Blaise Pascal invented the calculating device called the Pascaline. It had eight movable dials on wheels and could calculate sums up to eight figures long.
Both the abacus and Pascaline could perform only addition and subtraction operations. Later in the 17th century, Gottfried von Leibniz invented a device that was able to add, subtract, multiply, and divide. In 1819, Joseph Jacquard, a French weaver, discovered that the weaving instructions for his looms could be stored on cards with holes punched in them. While the cards moved through the loom in sequence, needles passed through the holes and picked up threads of the correct color and texture. A weaver could rearrange the cards and change the pattern being woven. In essence, the cards programmed a loom to produce patterns in cloth. The weaving industry may seem to have little in common with the computer industry. However, the idea of storing information by punching holes on a card proved to be of great importance in the later development of computers. In the early and mid-1800s, Charles Babbage, an English mathematician and physical scientist, designed two calculating machines: the difference engine and the analytical engine. The difference engine could perform complex operations such as squaring numbers automatically. Babbage built a prototype of the difference engine, but did not build the actual device. The first complete difference engine was completed in London in 2002, 153 years after it was designed. It consists of 8,000 parts, weighs five tons, and measures 11 feet long. A replica of the difference engine was completed in 2008 and is on display at the Computer History Museum in Mountain View, California (http://www.computerhistory.org/babbage/). Most of Babbage’s work is known through the writings of his colleague Ada Augusta, Countess of Lovelace. Augusta is considered the first computer programmer.
