The Chicago Manual of Style (CMS) is a highly regarded style guide for American English, dealing with questions of style, manuscript preparation, and, to a lesser degree, usage. (Note that in the publications world, style means punctuation, italicization, bolding, capitalization, tables, and so forth, and not prose style.)
The CMS is commonly used by publishers and editors as a last resort for questions of proper presentation of text.
It is published by the University of Chicago Press. The first edition was published by the University in 1906 under the title A Manual of Style. As of 2003, it is in its 15th edition. There is also a web-based version.
The ChicagoManual of Style appeared first in 1906 under the title Manual of Style: Being a compilation of the typographical rules in force at the University of Chicago Press, to which are appended specimens of type in use.
Thereafter, the ChicagoManual of Style began to lose a lot of its patronage: first with the introduction of the MLA style, and subsequently with the American Psychological Association introducing its own citationstyle.
The ChicagoManual of Style is still used in some social science publications and in most historical journals; the publications of the Organization of American Historians and the American Anthropological Association are two examples.
A publishing company's or periodical's house style is the collection of conventions set out in its internal style guide, or manual of style.
The Oxford Manual of Style: The 2003 work combines The Oxford Guide to Style and The Oxford Dictionary for Writers and Editors with the latter concentrating on common problems.
Two of the most widely used style guides in the United States are the ChicagoManual of Style and the Associated Press stylebook.