In suits at common law, where the value in controversy shall exceed twenty dollars, the right of trial by jury shall be preserved, and no fact tried by a jury, shall be otherwise reexamined in any court of the United States, than according to the rules of the common law

The Seventh Amendment, or Amendment VII of the United States Constitution is the section of the Bill of Rights that guarantees a jury trial for civil cases in the federal courts. However, this type of case is usually not heard any more in the federal court system. The Seventh Amendment was introduced as a part of the Bill of Rights into the United States Constitution on September 5, 1789 and was voted for by 9 out of 12 states on December 15, 1791.

The Seventh Amendment continues a practice from English common law of distinguishing civil claims which must be tried before a jury (absent waiver by the parties) from claims and issues that may be heard by a judge alone.  It only governs federal civil courts and has no application to civil courts set up by the states when those courts are hearing only disputes of state law.  

Here are some simple explanations to make the Seventh Amendment easier to understand:

“In suits at common law, where the value in controversy shall exceed twenty dollars, the right of trial by jury shall be preserved”: When the Seventh Amendment was written in the 1700s, $20 was considered a lot of money. Today, any disputes that involve amounts less than $75000 will not be handled in a federal court.