If you write to earn money, you need to know about copyright law.

Copyright provides the only legal protection you’ll have if your work is plagiarized, infringed upon, or otherwise exploited without your permission or fair compensation.

Indeed, without copyright most authors would earn nothing because no one would bother to pay them.

Here are 10 basic facts every author needs to know about copyright:

1. Copyright is the federal law that provides legal protection for works of authorship. This includes writings of all kinds, art, film, photography, video, websites, music (recordings and sheet music), software, choreography, and architectural designs. Don’t confuse copyrights with trademarks, which protect brand names, logos, and the like; or patents, which protect inventions.

2. Copyright protection starts automatically the moment you write anything down or create any other original work of authorship. However, you only get a copyright in words that you originate, not words (or other works) you copy from others. The copyright in any work you create lasts practically forever—for the rest of your life and then for 70 years after you die. When copyright expires, the work enters the public domain and may be freely used. Everything published in the United States before 1923 is in the public domain in the United States (but not necessarily in all foreign countries).

3. You are not required to place a copyright notice on your published work to obtain copyright protection. However, using a notice can increase the monetary damages you’re entitled to recover if someone infringes on your work. It can also deter others from stealing your work. A proper copyright notice consists of three elements: (1) the © symbol or the word “copyright,” (2) your name, (3) the year of publication. For example: © Stephen Fishman 2016. In books, notices are placed in a copyright page at the front of the work. Don’t include a notice on unpublished work—for example, a manuscript you submit to a publisher. This makes you look like a paranoid amateur.

4. You are not required to register your work with the United States Copyright Office to obtain copyright protection. However, you must register before you can file a copyright infringement lawsuit. If you register within three months of publication (or before an infringement occurs), you can get special statutory damages if you successfully sue someone for infringing on your work. If you have a publisher, it will ordinarily register the work for you. If you’re a self-publisher, you’ll need to register it yourself. Registration is easy. You can do it online at the Copyright Office’s website at www.copyright.gov. It costs as little as $35.

6. You are automatically the owner of all the copyright rights in any work you create on your own. These include the exclusive right to reproduce, distribute, perform, or display your work, or adapt it into new works. You are free to license or sell your copyright rights in any way you wish.

7. If you are an employee and create a work within the scope of your employment, your employer automatically owns all the copyright rights in the work. The same holds true if you are a nonemployee and sign a work for hire agreement with the person or entity who pays you for your work.

8. Copyright protection is limited: it only protects the particular words you use to express your ideas. Copyright does not protect ideas themselves; nor does it protect facts—whether scientific, historical, biographical, or news of the day.

9. The fair use privilege allows others to make limited use of your work without asking for your permission and without paying you—you can do the same with other authors’ words. Common examples of fair use include brief quotations in a review or scholarly work.

10. If someone copies your work without your permission, you have the right to sue them in federal court for copyright infringement. If successful, you can recover monetary damages and attorney fees. If the infringement occurred online, you can send a DMCA notice to the internet service provider (ISP) hosting the infringing material demanding that the work be removed—such notices are usually quite effective.