Board Foot – is actually a measurement of volume. A board foot is one square foot, one inch thick. To calculate board foot = width in inches x length in feet x thickness in inches.
Running Foot – is used in woodworking and means the same as a lineal foot. Refers to a one-dimensional measurement of length.
Square Foot – Is a unit of area in the imperial measurement system. A square measurement is the 2-dimensional derivative of a lineal measurement, so a square foot is defined as the area of a square with sides 1 foot in length.