In math, what does the term "regrouping" mean?

In mathematics, regrouping is the reorganization of numbers from one column to another to perform addition and subtraction equations. Typically, regrouping is referred to as “carrying” and “borrowing” a number.

For example, in the math equation 18 subtracted from 446 or 446-18, a number is borrowed from the tens column and transferred to the ones column. The regrouping helps complete subtraction in the equation. An example of regrouping for addition, or carrying, would be 19+3. To complete the equation, the “1” must be carried from the ones place to the tens place. In both examples, regrouping occurred because a number was moved from one column to the next.