Microsoft Excel Author: Wikipedia
Microsoft Excel (full name Microsoft Office Excel) is a spreadsheet program written and distributed by Microsoft for computers using the Microsoft Windows operating system and for Apple Macintosh computers. It features an intuitive interface and capable calculation and graphing tools which, along with aggressive marketing, have made Excel one of the most popular microcomputer applications to date. It is overwhelmingly the dominant spreadsheet application available for these platforms and has been so since version 5 in 1993 and its bundling as part of Microsoft Office.
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, in the words of Doug Klunder, '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 (numbered 2.0 to line-up with the Mac and bundled with a run-time Windows environment) 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.
Early in its life Excel became the target of a trademark lawsuit by another company already selling a software package named "Excel" in the finance industry. As the result of the dispute Microsoft was required to refer to the program as "Microsoft Excel" in all of its formal press releases and legal documents. However, over time this practice has been ignored, and Microsoft cleared up the issue permanently when they purchased the trademark to the other program. Microsoft also encouraged the use of the letters XL as shorthand for the program; while this is no longer common, the program's icon on Windows still consists of a stylized combination of the two letters, and the file extension of the default Excel format is .xls.
Excel offers many user interface tweaks over the earliest electronic spreadsheets; however, the essence remains the same as in the original spreadsheet, VisiCalc: the cells are organized in rows and columns, and contain data or formulas with relative or absolute references to other cells.
Excel was the first spreadsheet that allowed the user to define the appearance of spreadsheets (fonts, character attributes and cell appearance). It also introduced intelligent cell recomputation, where only cells dependent on the cell being modified are updated (previous spreadsheet programs recomputed everything all the time or waited for a specific user command). Excel has extensive graphing capabilities.
When first bundled into Microsoft Office in 1993, Microsoft Word and Microsoft PowerPoint had their GUIs redesigned for consistency with Excel, the killer app on the PC at the time.
Since 1993, Excel has included Visual Basic for Applications (VBA), a programming language based on Visual Basic which adds the ability to automate tasks in Excel and to provide user defined functions (UDF) for use in worksheets. VBA is a powerful addition to the application which, in later versions, includes a fully featured integrated development environment (IDE). Macro recording can produce VBA code replicating user actions, thus allowing simple automation of regular tasks. VBA allows the creation of forms and in-worksheet controls to communicate with the user. The language supports use (but not creation) of ActiveX (COM) DLL's; later versions add support for class modules allowing the use of basic object-oriented programming (OOP) techniques.
The automation functionality provided by VBA has caused Excel to become a target for macro viruses. This was a serious problem in the corporate world until antivirus products began to detect these viruses. Microsoft belatedly took steps to prevent the misuse by adding the ability to disable macros completely, to enable macros when opening a workbook or to trust all macros signed using a trusted certificate.
Versions 5.0 to 9.0 of Excel contain various Easter eggs, although since version 10 Microsoft has taken measures to eliminate such undocumented features from their products.