Many people think of computers as a new invention, and in reality it is very old. It is about 2000 years old .1 The first computer was the abacus. This invention was constructed of wood, two wires, and beads. It was a wooden rack with the two wires strung across it horizontally and the beads were strung across the wires. This was used for normal arithmetic uses. These type of computers are considered analog computers. Another analog computer was the circular slide rule. This was invented in 1621 by William Oughtred who was an English mathematician. This slid ruler was a mechanical device made of two rules, one sliding inside the other, and marked with many number scales. This slide ruler could do such calculations as division, multiplication, roots, and logarithms.
Soon after came some more advanced computers. In 1642 came Blaise Pascal's computer, the Pascaline. It was considered to be the first automatic calculator. It consisted of gears and interlocking cogs. It was so that you entered the numbers with dials. It was originally made for his father, a tax collector.2 Then he went on to build 50 more of these Pascaline's, but clerks would not uses them.3 They did this in fear that they would loose their jobs.4
Soon after there were many similar inventions. There was the Leibniz wheel that was invented by Gottfried Leibniz. It got its name