Visualizing vector fields is a difficult problem. Whereas scalar fields have a scalar value at each sample point, vector fields have an n-component vector (usually 2 or 3 components) at each point. Vector fields occur in applications such as computational fluid dynamics and typically represent the flow of a gas or liquid. Visualization of the field provides a way to better observe and understand the flow patterns.
Vector field visualization techniques can be grouped into 3 general classes: