Spreadsheet calculations tool like Microsoft Excel is the second important invention of human kind after the invention of the wheel. There is no need to spend days and weeks to do a large amount of calculations using just the paper or a pocket calculator. Excel brings all the tools and formulas you will ever need in order to prepare the most complex and difficult spreadsheet computation. Behind all above, Excel has a second powerful tool which is Visual Basic for Applications (VBA), that can do whatever data analysis and processing you can dream of, by operating directly with the content inside the cells and ranges. The programming code behind it is called macro and it can be attached to forms and buttons inside Excel spreadsheets in order to transform it in an ergonomic and human friendly data input and output. The beauty of all of this is that this application is used worldwide and the internet is full of useful information, know how and tutorials to solve whatever problem a beginner or advanced user may have.