Arguments

Arguments can be numbers, text, cell references, named ranges, arrays, formulas or even other functions.
Any arguments that are displayed in bold are required. The other arguments are optional.

If you insert a formula as an argument to a function you do not need to insert another equal sign (=). This is only necessary at the start of a formula.
If you want to insert a function as an argument to another function, this is referred to as a nested function and is covered in detail on the next page.
You can either type in the arguments directly or if the arguments are cell references you can select or drag the mouse over the relevant cells.
Displaying the function parentheses, commas and argument names can be useful is you are unfamiliar with the function arguments.
Pressing (Ctrl + Shift + A) when the insertion point is to the right of a function name will display this information.

Pressing (Ctrl + A) after you enter the name of function (e.g. =sum) will display the Function Arguments dialog box.