Avoid having to enter formulas into each cell of a document and use the $ Dollar Sign. Simply stated the dollar sign in an Excel cell reference serves just one purpose it tells Excel whether to change or not to change the reference when the formula is copied to other cells. Some examples of what you may have seen used in an excel spreadsheet include the following A1, $A$1, $A1, and A$1.

Watch this tutorial to learn about absolute and relative references