Microsoft originally marketed a spreadsheet program called Multiplan
in 1982, which was very popular on CP/M systems, but on MS-DOS
systems it lost popularity to Lotus 1-2-3.
This promoted development of a new spreadsheet called Excel which started with the intention to 'do everything 1-2-3 does and do it better'.
The first version of Excel was released for the Mac in 1985 and the first Windows version was released in November 1987.
Lotus was slow to bring 1-2-3 to Windows and by 1988 Excel had started to outsell 1-2-3 and helped Microsoft achieve the position of leading PC software developer.
This accomplishment, dethroning the king of the software world, solidified Microsoft as a valid competitor and showed its future of developing graphical software.
Microsoft pushed its advantage with regular new releases, every two years or so. The current version for the Windows platform is Excel 11, also called Microsoft Office Excel 2003. The current version for the Mac OS X platform is Microsoft Excel 2004.