The articles of the Macropædia are generally written by named contributors and have references, in contrast to the roughly 65,000 articles of the Micropædia that have no named contributor and no references. However, some parts of the Macropædia were written by the editorial staff of the Britannica; such editorial articles are identified by the initials "Ed."
The Macropædia is characterized by articles written by named authors and referencing sources, unlike the Micropædia which lacks this feature.  Some parts of the Macropædia were authored by the Britannica's editors, identified by the abbreviation "Ed."