MECHANICAL CALCULATING DEVICE

Abacus                       :- It was invented in 3000 B.C. It was used 

                                                           for calculating.

Napier’s Bone             :- It was invented in 1614 A.D. by

                                                          John Napier.

Pascaline                    :- It was invented in 1642 A.D. by  

                                              Blaise Pascal.

Stepped Recknor        :- It was invented in 1671 A.D. by

                                 Gott Fried Wilhelm  von Leibniz.

Jackquard’s Loom      :- It was invented in 1802 A.D. by  

                                               Joseph Marie Jackquard.

Difference Engine      :- It was invented in 1822 A.D. by  

                                               Charles Babbage.

Analytical Engine      :- It was invented in 1833 A.D. by

                                                           Charles Babbage.

Hollarith’s Tabulator :- It was invented in 1877 A.D. by

                                                           Hollarith’s Tabulator.