Automation provides benefits to virtually all of industry. Here are some examples:  Manufacturing, including food and pharmaceutical, chemical and petroleum, pulp and paper  Transportation, including automotive, aerospace, and rail  Utilities, including water and wastewater, oil and gas, electric power, and telecommunications  Defense  Facility operations, including security, environmental control, energy management, safety, and other building automation. There are also various software tools available in the market which can generate code for an application. The users only need to configure the tool and define the process. In other industries, automation is greatly improving productivity, saving time and cutting costs. Automation is evolving quickly and business intelligence in applications is a new form of high-quality automation. Automation covers applications ranging from a household thermostat controlling a boiler, to a large industrial control system with tens of thousands of input measurements and output control signals. In control complexity, it can range from simple on-off control to multi-variable high-level algorithms. In the simplest type of an automatic control loop, a controller compares a measured value of a process with a desired set value, and processes the resulting error signal to change some input to the process, in such a way that the process stays at its set point despite disturbances. This closed-loop control is an application of negative feedback to a system. The mathematical basis of control theory was begun in the 18th century and advanced rapidly in the 20th.