Equations of motion are mathematical formulas that describe the relationship between an object's position, velocity, acceleration, and time. They are essential in physics for predicting how an object will move under the influence of forces. The three main equations of motion apply to objects moving in a straight line with constant acceleration. These equations help solve problems related to kinematics, which is the study of motion without considering the forces causing it. They are commonly used in various fields, including engineering, astronomy, and sports science, to analyze and optimize movement and performance.