Copyright vs Trademark: What Each One Protects
Trademark is related to commercial matters and covers commercial products and the world of business. Copyright allows you to protect the text, image, book, story, software product or music piece that you have produced. Both empower you to protect what you own so no one else could use it without your permission, but what is protected is the ultimate difference.
An author's work is protected under copyright for 70 years after the 31st of December of the year he or she passes away. After that it becomes public domain. Sometimes we find products with no clear production date and author; in such cases a 120-year duration is considered. If maintained legally and properly, a trademark never ends and always belongs to you.
Copyright is an automatic right: a work is under your copyright immediately after you finish writing it, even if you haven't registered it yet. Registration lets you get involved in legal and financial transactions. A trademark is different; you must register it to own it.
Through copyright you own all aspects of a product, and anyone who wants to use it must ask your permission and pay a fee. A trademark has product categorization, so if someone uses your trademark in a different category, it is really hard to prove they took advantage of it.
There is a term called fair use: someone may discuss a part of your work only to some extent. Register a work immediately after it is created, before it is distributed. The Library of Congress is one of the best places to register international copyright, and it takes a few dollars for the form and file. Then you can license the work, and when a book is written, income doesn't simply come from the printed book: digital formats, games, movies and songs come out of it.