Technology is humanity’s knowledge of how to combine natural resources into useful tools. It can be anything from a simple tool, such as a crowbar or wooden spoon, to a complex machine, such as a particle accelerator or space station. It can also refer to computer software and business methods.
It is not just large technologies, such as nuclear reactors or agriculture, that are prone to side effects; many ordinary technologies have them, too. For instance, the refrigerator is liable to leak tiny amounts of a harmful gas, which eventually adds up. Moreover, the development of some technologies is not always desired by society at large because of their cost, potential risks to future generations, or impact on the environment. This is the concept behind the notion of appropriate technology, which was developed in the twentieth century.
The invention of a new technological device, system or method is often a lengthy process. This is because scientists and engineers must carefully examine the possibilities and implications of their inventions before they can move forward with them. This examination is usually done through a series of step-by-step experiments, which validate the underlying ideas and test their feasibility. Despite these efforts, it is rare that an original scientific result or engineer’s idea can be immediately translated into a usable technology, and apparently promising early technologies sometimes stall midway through their development. This is often due to a lack of funding and political obstacles.