It all adds up Computer life Computers are one of the most common gadgets we use in everyday life Most households in the developed world now own one and they are found in most schools and libraries We use them to store our music and photographs research homework shop play games and keep in touch with friends This versatile tool came about through our need to count things Count on it People have been counting for many thousands of years However doing so exactly and making calculations has always presented problems as people often lose track of what they are doing and make mistakes For this reason they have looked for ways to help them get calculations right The earliest known counting device is the beaded frame called the abacus which was invented about 3,000 years ago It is still used today in many parts of the world An abacus is not a calculator The operator The abacus is still used in many countries today Here a Korean storekeeper uses an abacus to find out the total price of the goods he is selling Each stage of a calculation is recorded by moving beads across the frame
John Napier Date of birth 1550 exact date not known Place of birth Edinburgh Scotland Profession Mathematician Greatest achievement The discovery of logarithms Interesting fact There is a story that Napier wanted to catch a servant who had been stealing He put a rooster in a dark shed and said that the bird would identify the guilty person Each man had to go and stroke the bird Napier guessing that the thief would be afraid to touch it had covered the bird with soot The thief would be the only one to emerge with clean hands Date of death April 4 1617 still has to do the math in his or her head but moving the beads to different positions on the frame helps keep track of each stage of a calculation Logarithms For thousands of years using an abacus was the best way to do calculations Then in 1614 John Napier a Scottish mathematician discovered logarithms Logarithms make it possible to turn multiplication into addition To multiply two numbers you look up the logarithm for each in list of numbers called a table and add them together Adding is easier than multiplying Logarithms had a huge impact on science The astronomer Johannes Kepler for example had written about how he was driven to distraction by the calculations he had to do Logarithms made his work and that of other scientists much simpler They remained in use for more than three centuries until mechanical calculators and eventually computers replaced them 7
