Ginkgo (Ginkgo biloba) is a large tree with fan-shaped leaves. The leaves are commonly included in supplements and taken by mouth for memory problems.

The ginkgo tree is thought to be one of the oldest living trees, dating back more than 200 million years. It is native to China, Japan, and Korea, but is also now grown in Europe and the United States. It seems to improve blood circulation, and might also act as an antioxidant to slow down changes in the brain.

Because ginkgo has been around for so long, people have used it for many purposes. It's commonly taken by mouth for memory and thought problems, anxiety, vision problems, and many other conditions.