Anabolic steroids are prescription-only meds, which are sometimes taken without medical advice, to increase muscle mass, improve athletic performance, and in many cases to enhance sexual performance. Note that steroids are class C drugs, which always need a doctor’s script, as they are artificial forms of testosterone, the male sex hormone.
It is legal to have anabolic steroids for personal use, bought at a pharmacy with a doctor’s script. However, it is illegal to sell them or give them to friends to use, and may even result in imprisonment if you break the law.