The $ means that the reference is absolute. For example $A$1 refers to cell
A1. You can copy that reference anywhere and it will refer to A1. If you use
A1, a relative reference, instead of $A$1, and you copy that it will change
to be relative to the cell into which you have copied it. For example if in
cell B1 you have the formula =$A$1 and copy that to cell B2 you will have
the formula =$A$1 in B2. If in B1 you have the formula =A1 and copy that to
cell B2 you will have the formula =A2 in B2. Relative references change,
absolute references do not. You can make the column and/or row absolute or
relative as in A1, $A1, A$1, $A$1
I suggest you acquire a book on Excel by an author such as John Walkenbach
to get a basic understanding of Excel.
Tyro