what is velocity of a particle?

Velocity of a particle is its speed and the direction in which it is moving.It can also be described as the instantaneous rate of change of the particle's distance traveled, and the direction in which the distance is changing.

velocity is generally defined as the distance travelled by a particle in a particular time interval ...........its formula is given asv=d/twhere v is velocity         d is distance travelled and         t is time interval.....    its units are - kmph , m/s read as kilometers per second and meters per second