Trademarks, copyrights and patents are all legal instruments available to protect an individual's or company's intellectual property rights, but each fulfils a different role and functions differently.
A trademark gives its owner sole rights to the use of the mark in commerce and preventing others from using a similar mark in connection with the same goods and services. Trademarks usually protect company names, logos or slogans. However, for example, the shape of the Coca-Cola bottle is also protected by a trademark, preventing others from manufacturing similar bottle shapes and enabling Coca-Cola to retain the rights to this unique shape that consumers arguably connect with the brand.
A copyright protects original (artistic) work and gives its owner rights for reproduction, distribution, control of public performance/display and creation of derivative works. For example, the copyright issued for a movie prevents others from copying and broadcasting the movie.
A patent gives its owner rights to exclude others from making or selling an item that makes use of the claims made in the patent - e.g. the mechanism describing a technological invention. The lightbulb, the computer and Bluetooth are all examples of patents.
You can learn more about the differences between common intellectual property protection mechanisms in this article.