Speed is a scalar quantity. Ex: I am driving at 30 mph.

Velocity is a vector quantity. Ex: I am driving at 30 mph due East.

Velocity is a vector. Speed is a scalar. The absolute value of velocity is speed.

Speed is a scalar and velocity is a vector but be careful if you are talking about instantaneous or average.  The speed of an object, at an instant, is the same as the magnitude of the velocity at that instant.   However, over a period of time

average speed = total distance/total time

and                                                                               

average velocity=change in position/change in time. 

Average speed and average velocity can be very different.

Velocity is speed with direction.  Speed is scalar (has magnitude) and velocity is a vector (has magnitude and direction)

Speed is a scalar, meaning it just has magnitude where velocity is a vector meaning it has magnitude and direction.