"Original works...fixed in any tangible medium of expression" can be protected by copyright and this protection begins as soon as the work is put into a medium of expression. Examples of things that you can copyright include:
This list provides just some of the types of works that can be protected by copyright, but there are many more types of works that can be protected as well.
Source: 17 U.S.C. §102(a)
You can't copyright everything, though you may be able to seek alternative legal protection, such as patents and trademarks. Here are some examples of things that can't be protected by copyright:
Source: 17 U.S.C. §102(b)
Copyright law protects the following exclusive rights of copyright holders:
Because these rights are exclusive, copyright holders have the right to either grant or deny others' requests to use their works.
Source: 17 U.S.C. §106
Since the Copyright Act of 1976, copyright protection now takes effect as soon as the work is fixed in a tangible medium of expression. You do not need to include a copyright notice on your work or register your copyright with the U.S. Copyright Office, but these two things are strongly recommended and the latter is required in order to file a copyright infringement suit.
Prior to the Copyright Act of 1976, copyright law required that in order to be protected by copyright, a work needed to be published with a copyright notice, such as the © symbol, and registered with the U.S. Copyright Office. This would provide copyright protection for 28 years; after 28 years, the copyright owner needed to renew their copyright. If they didn't, then the work was no longer protected.
This chart can help you determine if a work that was first published in the United States is still protected by copyright:
| Date Published | Contains Copyright Notice? | Did the Author(s) Register Work with Copyright Office? | Was Copyright Renewed After 28 Years? | Protected by Copyright? |
| Pre-1923 | Doesn't matter | Doesn't matter | Doesn't matter | No |
| Between 1923 and 1977 | No | No | Not applicable | No |
| Between 1923 and 1963 | Yes | Yes | No | No |
| Between 1923 and 1963 | Yes | Yes | Yes | Yes |
| Between 1964 and 1977 | Yes | Yes | Not applicable | Yes |
| Between 1978 and March 1, 1989 | No | No | Not applicable | No |
| Between 1978 and March 1, 1989 | No | Yes, within 5 years of publication | Not applicable | Yes |
| Between 1978 and March 1, 1989 | Yes | Yes | Not applicable | Yes |
| After March 1, 1989 | Doesn't matter | Doesn't matter | Not applicable | Yes |
Source: 17 U.S.C. §302-303
