MS Excel lets you reference data from different worksheets. To do this, use the worksheet title followed by an exclamation point. This way you can perform any calculation that you would with data or cell references, but within one worksheet.
For instance, in the image below, I took data from Cell B2 of my worksheet titled Software and placed it in cell C2 of the worksheet titled Hardware. I did this by typing =Software!B2 into cell C2 of the Hardware worksheet.