The dot or scalar product of two vectors is the product of their magnitudes and the cosine of the angle between them. It is the projection of one vector in the direction of another multiplied by the magnitude of the other. For instance, work is the dot product of force on an object and its displacement. When a force acts at an angle to the horizontal, only a part contributes to work. If it acts horizontally, it contributes fully to work. A vertical force cannot do any work in horizontal displacement. The scalar product of two vectors is commutative and distributive. The scalar product of the unit vector of one axis with another vanishes and with itself is one. Using these, the dot product of two vectors is the sum of the products of corresponding components. The angle between two vectors can be obtained using the dot product, and it is inverse cosine of the ratio of their dot product to the product of their magnitudes.