Machines have become an integral part of human life.
As we have read in our history books, early men, used to make small equipment or tools, to make their work easy. The preliminary work tools were wheel and axle for carrying heavy loads, wheel barrow, and sharp barks and so on. That day onwards, we are becoming more dependent on tools and machines and finally today, we are more than eighty per cent dependant on machines. Who can think of a single day without using a machine? People need not climb the steps, escalators are there, and more technically developed lifts are there. People even don’t know that how many spare parts are there in a machine, what complex structures are there. Many industries are built up, just because they are into manufacture of the machines, and plenty of labours are having their salaries on this industry. Education is also based on this; engineers are groomed up for the functioning of these small and big factories. From very small iron instruments to sophisticated computer hardware all the products of the techn