Linus Pauling and The Nature of the Chemical Bond: A Documentary History is comprised of three large sub-sections, each of which tells the story of the elucidation of chemical bond theory in a different way. Navigation between sub-sections may be achieved either through use of the links provided on the site homepage or through use of the links located in the header of each page within the site. Narrative - The first section - a forty-nine "chapter" Narrative - recounts the early years of chemical bond investigation primarily focusing on chemist Linus Pauling’s (1901-1994) research, which he later proclaimed as being his most important contribution to science. There are three components to each page of the Narrative. On the left is a table of contents, which grants easy navigation from chapter to chapter. In the center is the text of the Narrative - text which also includes links to an array of audio-visual materials as well as access to biographical information covering each of the major participants in the saga. (The Narrative text also utilizes "see also" links to documents which provide further information about the subject matter discussed on each page). Illustrations and quotations amplifying the narrative text are located on the right. Larger versions of all thumbnail illustrations may be accessed by clicking on the thumbnail. All Documents and Media - Linus Pauling and The Nature of the Chemical Bond: A Documentary History provides unprecedented access to over three hundred primary source materials, including letters, manuscripts, photographs, audio-visual materials and published papers. All documents which relate directly to the chemical bond may be accessed through the View All Documents and Media section through links entitled, " Correspondence ", " Key Participants ", " Published Papers ", " Manuscript Notes and Typescripts ", " Pictures and Illustrations ", " Quotes ", " Audio Clips " and " Video Clips ". As with the illustrations in the Narrative, the thumbnail images in View All Documents and Media may be enlarged by clicking on the thumbnail. Linus Pauling Day-by-Day - This section consists of a comprehensive account of all of Pauling's personal and professional endeavors in the years 1930 through 1939, when he was writing these seminal papers, and 1954, when he was awarded the Nobel prize in chemistry for these efforts. The information on Linus Pauling Day-by-Day is presented in calendar form, with scanned images of documents and photographs accompanying the text. The text and images are posted for each day of Pauling's activities during these featured eleven years. Originally launched in December 2004, a revised and expanded version of this website was released in February 2008. Along with a wide range of functionality and description improvements, content additions incorporated into the revision included over 1,400 pages of new manuscripts, papers and letters, 1.75 hours of additional audio excerpts and 2.5 hours of previously-unpublished video clips.