For over a decade we have been relying on the Windows calculator to perform simple tasks, but in Windows 7 Microsoft added more features that you might not even know about.
Calculator looks just the same as previous versions, even stored in the same location Start > All Programs > Accessories > Calculator. Open the Calculator and hit View. There’s a list of extra modes (Scientific, Statistical) and then unit conversions too. If you want to know how inches convert to microns, or calculate the difference between two dates, it can even calculate your monthly mortgage payments, the on-board Windows Calculator is more than up to the job.