A **scalar** is specified by magnitude and units only. For example, my car has **375 hp**, a "D" cell battery is **1.5 volts** or the cost of that article is **$10.00.**

In addition to magnitude and units, a **vector** must be specified with direction and point of application. For example, the force vector acting on the desk has a magnitude of **25 lbs**, a direction **down and to the right (45 degrees with the horizon),** and contacts the **left corner** of the desk.

A force vector is usually drawn to some convenient scale. We might draw the above 25 lb. force vector 1-1/4 inches long (each 1/4" would then represent 5 lbs of force).

If you wanted to add a force vector of 10 lbs acting downward on the opposite corner of the desk, you would show it as 1/2" long.