Acceleration is a fundamental concept in physics defined as the rate of change of velocity. Since velocity is a vector quantity, acceleration quantifies not only changes in speed, but also changes in direction. It is mathematically represented as the derivative of velocity with respect to time. In the International System of Units (SI), the standard unit for acceleration is meters per second squared ($\text{m}/\text{s}^2$). Understanding acceleration is crucial for analyzing motion, whether discussing objects accelerating uniformly in a straight line or describing more complex trajectories involving changes in curvature.