It uses active devices to control electron flow by amplification and rectification, which distinguishes it from classical electrical engineering which uses passive effects such as resistance, capacitance and inductance to control current flow. Electronics has had a major effect on the development of modern society.
The identification of the electron in 1897, along with the subsequent invention of the vacuum tube which could amplify and rectify small electrical signals, inaugurated the field of electronics and the electron age. This distinction started around 1906 with the invention by Lee De Forest of the triode, which made electrical amplification of weak radio signals and audio signals possible with a non-mechanical device. Until 1950, this field was called "radio technology" because its principal application was the design and theory of radio transmitters, receivers, and vacuum tubes.
Remotely operated underwater vehicles (ROVs) is the common accepted name for tethered underwater robots in the offshore industry. ROVs are unoccupied, highly maneuverable and operated by a person aboard a surface vessel. They are linked to the ship by a tether, a group of cables that carry electrical power, video and data signals back and forth between the operator and the vehicle. Most ROVs are equipped with at least a video camera and lights. Additional equipment may include sonars, magnetometers, a still camera, a manipulator or cutting arm, water samplers, and instruments that measure water clarity, light penetration and temperature.
The term originated during the early years of computing and referred to the large mechanical assembly that held the central processor and input/output complex. Later the term was used to distinguish high-end commercial machines from less powerful units which were often contained in smaller packages. Today, this term refers primarily to IBMSystem z9 mainframes, the lineal descendants of the System/360, but it is also used for the lineal descendents of the Burroughs large systems and the UNIVAC 1100/2200 series mainframes.