AP Stylebook, also known by its full name The Associated Press Stylebook and Briefing on Media Law, is an English grammar style and usage guide created by American journalists working for or connected with the Associated Press to standardize mass communications. Although it is sold as a guide for reporters, it has become the leading reference for most forms of public-facing corporate communication over the last half-century. The Stylebook offers a basic reference to grammar, punctuation and principles of reporting, including many definitions and rules for usage as well as styles for capitalization, abbreviation, spelling and numerals.