Financial Spreadsheets for Financial Math
Spreadsheets revolutionized financial mathematics by allowing people to create financial models that can automatically adjust for changes in financial values.
A simple example of this is a spreadsheet that amortizes a 30 year loan by months. Simply changing the value of the interest rate and recalculating the spreadsheet updates the entire amortization of 360 payments more quickly than a single payment may be calculated by hand to accomodate a change in interest rate. Similarly all values used as inputs can be modified and the entire financial model recalculated to accomodate the new values.