There are two types - Chinese and Siberian.
Chinese ginseng is a radish-like herb, usually found in supplements or as a tea. It is an aphrodisiac, and is good for energy and boosting immunity.
Siberian Ginseng is more of a shrub, and the roots or flowers can be used. It's cheaper than Chinese ginseng, but probably as effective.
Ginseng shouldn't be taken continuously.
Ginseng is a root herb widely use by the Chinese, Koreans and Japanese as medical remedies for numerous maladies. It can be use as a aphrodisiac but that is the wrong usage. It is use widely to maintain vitaly and energy for all male and females.