Angular velocity. In mathematics, "ω" (angular velocity) is a crucial concept, especially when describing circular motion or periodic phenomena. It represents the angle at which an object rotates around the center of a circle in a unit time, and it is a physical quantity that describes the rotation speed of an object. Specifically, when a particle moves in a circle, if it rotates through the angle of Δ θ within Δ t time, then "ω" is the ratio of Δ θ to Δ t, which not only reflects the rotating speed of the object, but also contains the information of the rotating direction, so ω is a vector. "Omega" is widely used in mathematics and physics. In mechanics, it can be used to describe the rotational motion of objects; In wave theory, the vibration frequency of waves can be expressed; In alternating current, it can describe the periodic change of current or voltage. In a word, "ω", as a representative symbol of angular velocity, plays an important role in mathematics and physics, which helps us to better understand and describe rotation and periodicity.