Wah is correct, but from the horse's mouth...
"About cell and range references
A reference identifies a cell or a range of cells on a worksheet and tells Microsoft Excel where to look for the values or data you want to use in a formula. With references, you can use data contained in different parts of a worksheet in one formula or use the value from one cell in several formulas. You can also refer to cells on other sheets in the same workbook, to other workbooks, and to data in other programs. References to cells in other workbooks are called external references. References to data in other programs are called remote references.
The A1 vs. the R1C1 reference style
The A1 reference style By default, Excel uses the A1 reference style, which refers to columns with letters (A through IV, for a total of 256 columns) and refers to rows with numbers (1 through 65536). These letters and numbers are called row and column headings. To refer to a cell, enter the column letter followed by the row number. For example, D50 refers to the cell at the intersection of column D and row 50. To refer to a range of cells, enter the reference for the cell in the upper-left corner of the range, a colon (
, and then the reference to the cell in the lower-right corner of the range. The following are examples of references.
To refer to Use
The cell in column A and row 10 A10
The range of cells in column A and rows 10 through 20 A10:A20
The range of cells in row 15 and columns B through E B15:E15
All cells in row 5 5:5
All cells in rows 5 through 10 5:10
All cells in column H H:H
All cells in columns H through J H:J
The range of cells in columns A through E and rows 10 through 20 A10:E20
The R1C1 reference style You can also use a reference style where both the rows and the columns on the worksheet are numbered. The R1C1 reference style is useful for computing row and column positions in macros. In the R1C1 style, Excel indicates the location of a cell with an "R" followed by a row number and a "C" followed by a column number. Learn about R1C1 references.
More information about references
Relative vs. absolute references Depending on the task you want to perform in Excel, you can use either relative cell references, which are references to cells relative to the position of the formula, or absolute references, which are cell references that always refer to cells in a specific location. If a dollar sign precedes the letter and/or number, such as $A$1, the column and/or row reference is absolute. Relative references automatically adjust when you copy them, and absolute references don't. More information about relative and absolute references.
Labels and names You can use the labels of columns and rows on a worksheet to refer to the cells within those columns and rows. Examples of labels are "Price," "Quantity," and "Total." Or you can create descriptive names to represent cells, ranges of cells, formulas, or constant values. More information about using labels or names in formulas.
3-D references If you want to analyze data in the same cell or range of cells on multiple worksheets within the workbook, use a 3-D reference. A 3-D reference includes the cell or range reference, preceded by a range of worksheet names. Excel uses any worksheets stored between the starting and ending names of the reference. For example, =SUM(Sheet2:Sheet13!B5) adds all the values contained in cell B5 on all the worksheets between and including Sheet 2 and Sheet 13. Learn about creating a 3-D reference."
i think there's a graphic missing but hope this helps.
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i whittled my hours with the boredom knife
and challenged my dreams with idle threats
i smoked strong coffee and read cigarettes
and drank up a cheap book on someone else's life...