Scalar and Vector quantities:
A quantity is a scalar if it is completely defined by its magnitude alone. For example: Length, area, and time. While quantity is said to be vector if it is completely defined when its magnitude and direction are specified. For example: Force, acceleration, and velocity.
Vector quantity can be represented by its direction, magnitude, point of application. Length of line is magnitude, inclination of line is the direction of, and in the figure given below C is called as point of application.
Figure
Here AC represent vector acting from point A to C T = Tail of vector
H = Head of vector
Q = Direction of vector
Arrow represents Sense.