The IBM Style Guide: Conventions for Writers and Editors

Throughout, the authors illustrate the guidance with many examples of correct and incorrect usage.
Writers and editors will find authoritative guidance on issues ranging from structuring information to writing usable procedures to presenting web addresses to handling cultural sensitivities.
The guidelines cover these topics:
Using language and grammar to write clearly and consistently
Applying punctuation marks and special characters correctly
Formatting, organizing, and structuring information so that it is easy to find and use
Using footnotes, cross-references, and links to point readers to valuable, related information
Presenting numerical information clearly
Documenting computer interfaces to make it easy for users to achieve their goals
Writing for diverse audiences, including guidelines for improving accessibility
Preparing clear and effective glossaries and indexes
The IBM Style Guide can help any organization or individual create and manage content more effectively. The guidelines are especially valuable for businesses that have not previously adopted a corporate style guide, for anyone who writes or edits for IBM as an employee or outside contractor, and for anyone who uses modern approaches to information architecture.

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