An often overlooked but useful feature of Windows is the inbuilt calculator. Windows has included a Calculator since version 1.0. The latest versions of Windows, version 7 and 8 share the same calculator functionality.
The Calculator can do so much more than just basic arithmetic. You can toggle between Standard, Scientific, Programmer, and even Statistics modes. The Calculator also includes other tools that are beyond the scope of the calculation modes. Things like light weight conversion or calculating the distance from one specified day to another one. Going a little further than what you would normally need from a calculator, it also offers to help you with calculating mortgage values, vehicle lease and car consumption.
Where to Find the Calculator in Windows 7 & Windows 8:
In Windows 8 the Calculator is part of the Windows Accessories. To find it, in Windows 8 go to the Start screen right click (or swipe from the bottom) and select All apps. You will find it under Windows Accessories.
In Windows 7 you can access it by going to Start Menu – > Accessories -> Calculator.