A machine is a mechanical structure that performs a task. Physicists call this work a force. So we can consider a machine as a device that transfers a force from one point to another by increasing the distance or speed or intensity or direction in which it is transmitted. Any machine is created and used to facilitate both the product chain and the assembly line.

There are 2 types of machines: simple ones, such as a wheel and an axle, and complex ones, such as scissors. Renaissance scientists considered 5 simple machines – lever, screw, inclined plane, pulley and wheel and axle. These types of machines, despite having few moving parts, need energy to function. A complex machine results from the union of 2 or more simple machines in order to create a single mechanism. For example, a bicycle is a complex machine because it is composed of a pulley and a system of pedals.

All types of machines need energy to function. If in the past, human and animal strength were the main sources of energy, with the Industrial Revolution man started to exploit natural resources in order to improve the performance of machines. In parallel, the operation of a machine may involve the transformation of chemical, thermal, electrical or nuclear energy into mechanical energy, or vice versa, such as the diesel engine or steam engine.

Nowadays, some machines are associated with electronic systems in order to improve efficiency on the production line. Electronics, when compared to mechanics, have a higher degree of reliability. Therefore, many companies adopt robots – a complex machine made up of several simple machines and a set of electronic systems in order to perform a task – with the long-term aim of increasing profit.