A more thorough explanation:

The United States Court of Appeals for the Federal Circuit is a court that hears appeals in patent cases and various actions against the United States to recover damages. It also hears cases from other courts and administrative agencies.

The Court was created in 1982 by merging the Court of Customs and Patent Appeals and the U.S. Court of Claims. Its purpose was to end forum-shopping in patent suits, settle differences in patent-law doctrines among the circuits, and allow a single forum to develop the expertise needed to rule on complex technological questions that arise in patent suits.

For example, if a company sues another company for infringing on their patent, and the case is appealed, it may be heard by the United States Court of Appeals for the Federal Circuit. The Court would then make a decision on the case based on patent law and other relevant factors.

The United States Court of Appeals for the Federal Circuit is often shortened to "federal circuit" and abbreviated as CAFC or Fed. Cir.