Functions

Functions are predefined formulas.

Examples of this are:

1. PRODUCT function - used to find the product (multiplication)
2. AVERAGE function - find the average
3. COUNTA function - count the cells which aren't empty  as well as the number of arguments that contain values.

E R R O R !

Functions do not always work out perfectly...

These errors will show up if you do something wrong:

1. #N/A - data not found
2. #DIV/0! - occurs when a formula tries to divide by zero
3. #NULL! - occurs when the two or more cell references are not separated correctly in a formula
4. #REF! - An invalid cell reference error message occurs when a spreadsheet formula contains incorrect cell references
5. #NAME! -  error occurs when Excel does not recognize text in a formula
6. #### - column isn't wide enough to display the value
7. #NUM! -  pass an invalid argument to a function 
8. #VALUE! - a formula has the wrong type of argument