It is not unusual for people to get confused when it comes to knowing the difference between the job of a publisher and that of a printer. Though they both are involved in the production of books, they have very distinctive roles in the book production chain.

Publishers edit. This means publishers are responsible for content.

They are involved in the various processes of editing a manuscript – proofreading, designing, layout, reviewing, copy editing, designing, preparing manuscripts for printing etc. They can take 3 to 12 months before they are done

Printers print. That means they have machines that print, bind and trim books. Printers do not assume responsibility for content. They just print what they are given.
A publisher generally accepts all the financial responsibility for the production and promotion of the books. A printer is paid by the publisher to print.
Publishers make money from the sale of books.

Publishers may distribute or sell books to book distributors

Printers do not sell books. Their revenue is gotten from the payments from publishers

Printers do no distribute or warehouse books

Publishers are all about books Printers are all about printing on materials including books, flyers, brochures, cards, clothing etc.
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