A patent protects an invention. If you have a patent, only you can make, use or sell the invention. You decide who can use it. If someone else does use it, they have to give you money.

Not everyone can get patents. Before the 1860s, most African-Americans were enslaved. Enslaved people were not allowed to get patents. But this didn't stop them from inventing new things.

Papan was enslaved. He lived 300 years ago. He made a new cure for skin diseases. It worked very well, and lawmakers freed him. They wanted him to work as a doctor and cure people.

Not all African-Americans were enslaved people. Here are three black inventors from 300 years ago. They were all free men.

Benjamin Banneker

Benjamin Banneker was born in 1731. He taught himself math. He was able to make a new clock out of wood.

Later, Mr. Banneker wrote "Banneker's Almanac." Almanacs were books that had useful information. They said when the sun sets and rises, for example.

Mr. Banneker gave a copy to Thomas Jefferson. Jefferson was a Founding Father. Mr. Banneker asked him to give African-Americans equal rights.

James Forten

James Forten was born in 1766. He served in the U.S. Navy and fought in the Revolutionary War. Americans were ruled by Britain at the time. In the Revolutionary War, Americans fought to be free.

After the war, Mr. Forten became a sailmaker. He created a tool to handle ship sails. He got a patent for his invention and became rich. Mr. Forten used his money to support women's rights and to end slavery.

George Peake

George Peake was born in 1722. He also fought in the Revolutionary War. Mr. Peake invented a machine for grinding corn. He did not patent his invention.