Prime objective of this lecture is to present on Long Division. Here briefly describe on Divide, Multiply, Subtract and Bring Down. DMSB is the order of operations for division. It stands for Divide, Multiply, Subtract, Bring Down. Long Division is an arithmetical division in which the divisor has two or more figures, and a series of steps is made as successive groups of digits of the dividend are divided by the divisor, to avoid excessive mental calculation.