The developer of MS Excel is the software giant Microsoft. Microsoft is also known all over the world for its operating system such as Windows 98, Xp, and Vista. 'MS' is MS Excel itself stands for Microsoft.
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Excel is a spreadsheet developed by Microsoft but is by no means the first spreadsheet.
The very first spreadsheet was developed (or invented) by Dan Bricklin and Bob Frankston called VisiCalc. VisiCalc was a spreadsheet written to operate on the Apple II computer and was released in 1979. The program was sold to Lotus who developed Lotus 123 from the VisiCalc principle. Lotus 123 was released in 1983.
Excel, first released in 1987, is a development of the early spreadsheets and therefore cannot strictly be classified as an invention. Excel is far more powerful than VisiCalc but that is also a result of development over the years that Microsoft have been working on the product, and the increase in computing power.
Dan Bricklin and Bob Frankston never patented the product because software patents were almost unheard of in the 70s.