An absolute reference is a reference in the formula, which does not change when copying to another cell. By using absolute references the cell address is kept when copied to other cells. This is a powerful tool when you are working on a spreadsheet with lots of data.
To create an absolute reference, place the weight sign ($) before the column (letter) or line (number) that you do not want to change. For example: the cell reference $ C $ 4 is an absolute reference; however cell reference C4 is a relative reference. If you copy a formula that contains the absolute reference $ C $ 4 to another cell, the cell reference $ C $ 4 does not change, but if you copy a formula that contains the relative reference C4 to another cell, the C4 reference does change.
