This video introduces the concept of phased arrays. An array refers to multiple sensors, arranged in some configuration, that act together to produce a desired sensor pattern. With a phased array, we can electronically steer that pattern without having to physically move the array simply by adjusting the phase of the signals to each individual element. Commonly, an array is made up of antennas like for wireless communication and radar, but the general concept can be applied to different elements as long as they measure or emit waves. For example, a speaker and microphone array that is used for sonar and acoustic imaging is a type of phased array. In each of these applications, we have to form a beam and we have to be able to move that beam around. And we can do that with phased array systems.