Describes the motion of points, objects and systems of groups of objects, without reference to the causes of motion.
The symbol a stands for the acceleration of the object. And the symbol v stands for the instantaneous velocity of the object.
The derivative of displacement with time is velocity ( v = ds/dt ). The derivative of velocity with time is acceleration ( a = dv/dt ).
t: the time, measured in seconds [s].
x(t): the position as a function of time, also known as the equation of motion.
v(t): the velocity. a(t): the acceleration. xi=x(0),vi=v(0): the initial conditions.
Finally it is part of calculus.
Kinematics