A vector describes the relative displacement from one point in the plane to another. It is written in the form where the first (top) component represents the horizontal displacement (parallel to the -axis) and the second represents the vertical displacement (parallel to the -axis). Positive numbers represent displacement in the positive direction, negative in the opposite.
Vectors can be added, subtracted, and scaled by applying these operations component by component:
Two vectors are parallel if one is a scale multiple of the other.