Microsoft Word is Microsoft's flagship word processing software. It was first released in 1983 under the name Multi-Tool Word for Xenix systems.Versions were later written for several other platforms including IBM PCs running DOS (1983), the Apple Macintosh (1984), SCO UNIX, OS/2 and Microsoft Windows (1989). It is a component of the Microsoft Office system; however, it is also sold as a standalone product and included in Microsoft Works Suite. Beginning with the 2003 version, the branding was revised to emphasize Word's identity as a component within the Office suite: Microsoft began calling it Microsoft Office Word instead of merely Microsoft Word. The latest release is Word 2007.
File formats
Although the familiar ".doc" extension has been used in many different versions of Word, it actually encompasses four distinct file formats:
1. Word for DOS
2. Word for Windows 1 and 2; Word 4 and 5 for Mac
3. Word 6 and Word 95; Word 6 for Mac
4. Word 97, 2000, 2002, and 2003; Word 98, 2001, X, and 2004 for Mac
The newer ".docx" extension signifies Office Open XML and is used by Word 2007 for Windows and Word 2008 for the Macintosh.
Binary formats and handling
Word document formats (.DOC) as of the early 2000s were a de facto standard of document file formats due to their popularity. Though usually just referred to as "Word document format", this term refers primarily to the range of formats used by default in Word version 2–2003. In addition to the default Word binary formats, there are actually a number of optional alternate file formats that Microsoft has used over the years. Rich Text Format (RTF) was an early effort to create a format for interchanging formatted text between applications. RTF remains an optional format for Word that retains most formatting and all content of the original document. Later, after HTML appeared, Word supported an HTML derivative as an additional full-fidelity roundtrip format similar to RTF, with the additional capability that the file could be viewed in a web browser. Word 2007 uses the new Microsoft Office Open XML format as its default format, but retains the older Word 97–2003 format as an option. It also supports (for output only) PDF and XPS format.
The document formats of the various versions change in subtle and not so subtle ways; formatting created in newer versions does not always survive when viewed in older versions of the program, nearly always because that capability does not exist in the previous version. Wordart also changed drastically in a recent version causing problems with documents that used it when moving in either direction. The DOC format's specifications are not available for public download but can be received by writing to Microsoft directly and signing an agreement
Microsoft Word 95-2003 implemented OLE (Object Linking and Embedding) to manage the structure of its file format, easily identifiable by the .doc extension. OLE behaves rather like a conventional hard drive filesystem, and is made up of several key components. Each word document is composed of so called "big blocks" which are almost always (but do not have to be) 512-byte chunks, hence a Word documents filesize will always be a multiple of 512. "Storages" are analogues of the directory on a disk drive, and point to other storages or "streams" which are similar to files on a disk. The text in a Word document is always contained in the "WordDocument" stream. The first big block in a Word document, known as the "header" block, provides important information as to the location of the major data structures in the document. "Property storages" provide metadata about the storages and streams in a .doc file, such as where it begins and its name and so forth. The "File information block" contains information about where the text in a word document starts, ends, what version of Word created the document and so forth. Needless to say, Word documents are far more complex than perhaps initially expected, perhaps necessarily, or in part to prevent third-parties designing interoperable applications.
People who do not use MS Office sometimes find it difficult to use a Word document. Various solutions have been created. Since the formats are de facto standards, many word processors such as AbiWord or OpenOffice.org Writer need file import and export filters for Microsoft Word's document file format to compete. Furthermore, there is Apache Jakarta POI, which is an open-source Java library that aims to read and write Word's binary file. Macintosh users had file translater filters such as MacLinkPro with the ability to interconvert Word, Works, WordPerfect, NisysWriter and many other formats. Most of this interoperability is achieved through reverse engineering since documentation of the Word 1.0-2003 file format, while available to partners, is not publicly released. The Word 2007 file format, however, is publicly documented.
For the last 10 years Microsoft has also made available freeware viewer programs, but only for Windows, that can read Word documents without a full version of the MS Word software. Microsoft has also provided converters that enable different versions of Word to import and export to older Word versions and other formats and converters for older Word versions to read documents created in newer Word formats.The whole Office product range is covered by the Office Converter Pack for Office 97–2003 and Office Compatibility Pack for Office 2000–2007 since the release of Office 2007.
Features
Normal.dot
Normal.dot is the master template from which all Word documents are created. It is one of the most important files in Microsoft Word. It determines the margin defaults as well as the layout of the text and font defaults. Although normal.dot is already set with certain defaults, the user can change normal.dot to new defaults. This will change other documents which were created using the template and saved with the option to automatically update the formatting styles.
Macros
Like other Microsoft Office documents, Word files can include advanced macros and even embedded programs. The language was originally WordBasic, but changed to Visual Basic for Applications as of Word 97.
This extensive functionality can also be used to run and propagate viruses in documents. The tendency for people to exchange Word documents via email, USB key, and floppy makes this an especially attractive vector. A prominent example is the Melissa worm, but countless others have existed in the wild. Some anti-virus software can detect and clean common macro viruses, and firewalls may prevent worms from transmitting themselves to other systems.
These Macro viri are the only known cross-platform threats between Windows and Macintosh computers and they were the only infection vectors to affect any MacOS X system up until the advent of video codec trojans in 2007. Microsoft's released patches for Word X and Word 2004 effectively eliminated the Macro problem on the Mac by 2006.
Word's macro security setting, which regulates when macros may execute, can be adjusted by the user, but in the most recent versions of Word, is set to HIGH by default, generally reducing the risk from macro-based viruses, which have become uncommon.
Layout issues
As of Word 2007 for Windows (and Word 2004 for Macintosh), the program has been unable to handle ligatures defined in TrueType fonts: those ligature glyphs with Unicode codepoints may be inserted manually, but are not recognized by Word for what they are, breaking spellchecking, while custom ligatures present in the font are not accessible at all. Other layout deficiencies of Word include the inability to set crop marks or thin spaces. Various third-party workaround utilities have been developed.[9] Similarly, combining diacritics are handled poorly: Word 2003 has "improved support", but many diacritics are still misplaced, even if a precomposed glyph is present in the font. Additionally, as of Word 2002, Word does automatic font substitution when it finds a character in a document that does not exist in the font specified. It is impossible to deactivate this, making it very difficult to spot when a glyph used is missing from the font in use.
In Word 2004 for Macintosh, complex scripts support was inferior even to Word 97, and Word does not support Apple Advanced Typography features like ligatures or glyph variants
Bullets and numbering
Users report that Word's bulleting and numbering system is highly problematic. Particularly troublesome is Word's system for restarting numbering.However, the Bullets and Numbering system has been significantly overhauled for Office 2007, which should reduce the severity of these problems.
Creating Tables
Users can also create tables in MS Word. Depending on the version you have, formulas can also be computed.
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