To know if you need a copyright or if your products are already protected, you need to know what exactly a copyright is. In a basic sense, a copyright gives the creator of an original work the exclusive right to sell it, reproduce it and publish it. United States copyright law protects individuals who have created works such as photographs, videos of live performances, movies, software and more.
It's important to note that any ideas, techniques or other expressions have to be in material form to be protected. That means that you must write down a story, draw an image that you're thinking of or otherwise place the product in tangible form for it to be protected through copyright law.
Why does copyright law exist?
Copyright law exists to protect the effort, time and creativity put into a work by the creator. The copyright owner then obtains the exclusive rights to the work, allowing them to sell it or use it in the ways they see fit.
Another huge benefit of a copyright is that the copyright holder can choose to authorize others to use their work. This allows them to sell pieces or to temporarily authorize rights to the works in exchange for royalties or other benefits.
There is an exclusion to the rule that the creator typically obtains the copyright, and that is if they have created a work for a company or individual that they were hired by. The work is then called "work made for hire" and usually does not allow for the creator to retain the rights. A good example of this would be to look at the animators and designers who make a popular character for Disney. They don't retain the rights to the character. Instead, Disney has the authority to do anything they want with the character, since the designer was hired to create for the company exclusively.
The same can apply to written work, poems, software and other works made while under the employment of a company or when working for hire with a client.
There are exceptions to be made for most rules in law, so if you have created a work and want to guarantee that you will retain possession of it and all the rights that go with it, you should speak with your New York attorney. Your attorney can help guide you toward protecting your work through a copyright when it's necessary.