Microsoft Excel (full name Microsoft Office Excel) is a spreadsheet application written and distributed by Microsoft for Microsoft Windows and Mac OS X. It features calculation, graphing tools, pivot tables and a macro programming language called VBA (Visual Basic for Applications). It has been the most widely used spreadsheet application available for these platforms since version 5 in 1993. Excel is part of Microsoft Office.
History
Excel 2.0
Microsoft originally marketed a spreadsheet program called Multiplan in 1982, which became very popular on CP/M systems, but on MS-DOS systems it lost popularity to Lotus 1-2-3. Microsoft released the first version of Excel for the Mac in 1985, and the first Windows version (numbered 2.05 to line up with the Mac and bundled with a run-time Windows environment) 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 GUI software. Microsoft pushed its advantage with regular new releases, every two years or so. The current version for the Windows platform is Excel 12, also called Microsoft Office Excel 2007. The current version for the Mac OS X platform is Microsoft Excel 2008.
Early in 1993, 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 of 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 program displays cells organized in rows and columns, and each cell contains data or a formula, 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, and enables users to perform mail merge.
When Microsoft first bundled Microsoft Word and Microsoft PowerPoint into Microsoft Office in 1993, those applications 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 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.
Excel 5.0
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.
Excel 2000
See also: Microsoft Office 2000
For most users, one of the most obvious changes introduced with Excel 2000 (and the rest of the Office 2000 suite) was a clipboard that could hold multiple objects at once. Another noticeable change was that the Office Assistant, whose frequent unsolicited appearance in Excel 97 had annoyed many users, was changed to be less intrusive.
Versions for windows:
- 1987 Excel 2.0 for Windows.
- 1990 Excel 3.0.
- 1992 Excel 4.0.
- 1993 Excel 5.0 (Office 4.2 & 4.3, also a 32-bit version for Windows NT only on the PowerPC, Alpha, and MIPS architectures).
- 1995 Excel for Windows 95 (version 7.0) - included in Office 95.
- 1997 Excel 97 - included in Office 97 (for x86 and Alpha). This version of Excel includes a flight simulator as an Easter Egg.
- 1999 Excel 2000 (version 9.0) included in Office 2000.
- 2001 Excel 2002 (version 10) included in Office XP.
- 2003 Excel 2003 (version 11) included in Office 2003.
- 2007 Excel 2007 (version 12) included in Office 2007.
- Notice: There is no MS-DOS version of Excel 1.0 for Windows, because the Windows version was introduced at the time the Mac version was up to 2.0.
- Notice: There is no Excel 6.0, because the Windows 95 version was launched with Word 7. All the Office 95 & Office 4.X products have OLE 2 capacity — moving data automatically from various programs — and Excel 7 should show that it was contemporary with Word 7.
for Apple Macintosh:
- 1985 Excel 1.0.
- 1988 Excel 1.5.
- 1989 Excel 2.2.
- 1990 Excel 3.0.
- 1992 Excel 4.0.
- 1993 Excel 5.0 (Office 4.X—Motorola 68000 version and first PowerPC version).
- 1998 Excel 8.0 (Office '98).
- 2000 Excel 9.0 (Office 2001).
- 2001 Excel 10.0 (Office v. X).
- 2004 Excel 11.0 (part of Office 2004 for Mac).
- 2008 Excel 12.0 (part of Office 2008 for Mac).
for OS/2
- 1989 Excel 2.2
- 1990 Excel 2.3
- 1991 Excel 3.0
Versions of Excel up to 7.0 had a limitation in the size of their data sets of 16K (2^14=16384) rows. Versions 8.0 through 11.0 could handle 65K (2^16=65536) rows and 256 columns (2^8 as label 'IV'). Version 12.0 can handle 1M (2^20=1048576) rows, and 16384 (2^14 as label 'XFD') columns.
File formats
Excel Spreadsheet Filename extension .xls
Internet media type application/vnd.ms-excel
Uniform Type Identifier com.microsoft.excel.xls
Developed by Microsoft
Type of format Spreadsheet
Microsoft Excel up until 2007 version used a proprietary binary file format called Binary Interchange File Format (BIFF) as its primary format. Excel 2007 uses Office Open XML as its primary file format, an XML-based format that followed after a previous XML-based format called "XML Spreadsheet" ("XMLSS"), first introduced in Excel 2002. The latter format is not able to encode VBA macros.
Although supporting and encouraging the use of new XML-based formats as replacements, Excel 2007 remained backwards-compatible with the traditional, binary formats. In addition, most versions of Microsoft Excel can read CSV, DBF, SYLK, DIF, and other legacy formats. Support for some older file formats were removed in Excel 2007 . The file formats were mainly from DOS based programs.
The new Excel 2007 formats are:
New Excel 2007 formats Format Extension Description
Excel Workbook .xlsx The default Excel 2007 workbook format. In reality a ZIP compressed archive with a directory structure of XML text documents. Functions as the primary replacement for the former binary .xls format, although it does not support Excel macros for security reasons.
Excel Macro-enabled Workbook .xlsm As Excel Workbook, but with macro support.
Excel Binary Workbook .xlsb As Excel Macro-enabled Workbook, but storing information in binary form rather than XML documents for opening and saving documents more quickly and efficiently. Intended especially for very large documents with tens of thousands of rows, and/or several hundreds of columns.
Excel Macro-enabled Template .xltm A template document that forms a basis for actual workbooks, with macro support. The replacement for the old .xlt format.
Excel Add-in .xlam Excel add-in to add extra functionality and tools. Inherent macro support because of the file purpose.
By: Andreas.W Source=http://en.wikipedia.org/wiki/Microsoft_Excel
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