The correct answer to this question is Switch. Switches change flows of electrical circuits. The word switch itself helps understand the meaning of it because it means electrical power. Gates are another word that may be referred to.
Normally, when this word is used, it is for mathematical terms. Switches are all around us, especially in this age of technology. One example is a computer, which many of us use all the time. In computers, there are a number of switches.
These switches act as gates that allow the computer to perform basic functions. There are many types of switches like DIP switch and reed switch.