International standardISO 2145 defines a typographic convention for the "numbering of divisions and subdivisions in written documents". It applies to any kind of document, including manuscripts, books, journal articles, and standards.
The main divisions are numbered continuously starting from 1.
Each main division (first level) can be divided further into subdivisions (second level), which are equally continuously numbered. This can be continued for further levels of subdivision.
Afull stop is placed between numbers that designate subdivisions of different levels. No full stop is placed after the number that designates the final subdivision.
A number 0 (zero) can be assigned to the first division of each level if it forms anintroduction,preface,foreword, or the like.
All standardLaTeX document classes generatechapter,section, subsection, figure, table, etc. numbers as defined by ISO 2145.
As of 2003, allMicrosoft Word versions were by default set up to add a full stop after the final section number. This does not conform to ISO 2145. However, users can change style settings to match the ISO standard. InWord 16, for example, in the “Styles pane”, right-clicking on the relevant heading style to select “Modify Style”, then following Format/Numbering.../Outline Numbered leads to a graphical choice of numbering styles that includes one closely matching ISO 2145, which can then be customized to remove any trailing dot.
