Define (a) Abacus, (b) Pascaline, (c) Analytical Engine, (d) Punch card.

Abacus: One of the first devices used for mechanical computations was the abacus. It usually consist of a rectangular frame divided into two parts by mid bar enclosing rods on which balls or beads are moved. The upper part is called heaven consists of two beads and each bead equal to value 5 and lower part is called earth, consists of five beads and each bead equal to value of 1. A person moves the beads to perform arithmetic calculations.

(b) Pascaline: Blaise Pascal, a French Mathematician invented the first mechanical calculating machine called Pascaline in 1642 when he was 19 years old. The Pascaline is a numerical wheel calculator which had 8 movable dials. It worked on the principle of rotating wheels. This machine could only do addition, subtraction and multiplication by repeated addition and division by repeated subtraction. The numbers of calculating capacity of Pascaline was 9,99,99,999.

(c) Analytical Engine: In 1833, an English mathematician named Charles Babbage began designing a new general purpose calculating device, called the Analytical Engine. The idea of Babbage engine can be summarised below.

a) Data and program instructions are fed by suitable device called punched card.

b) Storage device for data and instruction.

c) The unit for calculation called mill.

d) A suitable output device to display result.

Punch Card: The punch card is a recording medium for holding information for use by automated data processing machines. Herman Hollerith took the Jacquard punched card concept a stage further when he applied the technique to counting and sorting in the American Census of 1890. In the first generation of computing, from the 1920s into the 1950s, punch cards were the primary medium for data storage and processing. They were an important medium, particularly for data input.