The Anatomy of a Function

Each function has two parts: the name of the function and its arguments. The name of a function always appears in uppercase letters and describes what the function does. For example, the AVERAGE function calculates the average of all the arguments included with the function.

Arguments are the numbers, cell references, worksheet names, or other information that a function needs to calculate a value for you. An argument can be any one of the following:

• Numbers, such as -5, 11, and 63.2.
• Text, such as "a", "Word", and "w/punc." If the text you want to use contains quotation marks, use two double quotation marks (""text"") for each double quotation mark.
• Logical values, such as TRUE or FALSE, or a statement that creates a logical value when calculated, such as B10>20.
• Error values, such as #REF!.
• References, such as D12 or C4:C6.

Arguments follow the name of the function and are enclosed in parentheses. Multiple arguments are separated by commas. For example, if you wanted to find the average of the numbers 5, 11, and 63, plus the numbers included in the range C4:C6, you would enter the AVERAGE function and the following arguments into a cell:

=AVERAGE(5, 11, 63, C4:C6)

When you enter a function, you must precede it with an equal sign (=).

The functions, equal sign, and numbers, text, or references entered in a cell are referred to as a formula. After you enter a formula, Microsoft Excel calculates the formula and displays the resulting value in the cell. However, your formula isn't erased when a cell displays the value calculated from the formula. You can see your formula by selecting the cell and looking at the formula bar. Microsoft Excel recalculates the formula every time an argument changes.