The creator of a source is often not the same entity that publishes, or makes public and accessible, the source. That is the role of the PUBLISHER, who is in charge of making and/or distributing the source to its intended audience.
A Publisher is usually a company or organization, not a person.
In the case where the Container and the Publisher are the same name, as is the case in many periodicals and websites, then the publisher is usually omitted.
Books
A book publisher is the entity that designs, prints, and distributes the material. For more information on how to find the publisher, click HERE.
In the case that there is a separate printing press to the publisher, only the main publisher is included. When the publisher is part of a much larger company, the publisher that appears on the Title Page is the entity that counts.
Other Printed Material
In periodicals (magazines and newspapers) the publisher is usually omitted.
In comic books the publisher is included.
For official documents the branch in charge of printing the material is cited. In the case that the author of the source is already the publishing branch, the Publisher is omitted. This is true for material produced by organizations, schools and universities, etc...
Websites
The publisher is the person, company or organization that hosts, or runs, the website.
If the Container and the Publisher is the same name, then the Publisher is omitted.
However, if the website name is different from the name of the organization that runs it, then you must include both. For more information on how to find the Publisher of a website, click HERE.
Audiovisual Material
In non-text formats, the Publisher is replaced by the Producer.
Film and Television: The Production Company is the Publisher
Music: the Publisher is the Record Company
Objects: the Brand company is the Publisher