This single species has thousands of varieties and strains. Varieties with a very low content of THC are eligible for industrial uses. We make all sorts of things with cannabis, like clothes, paper, plastics, insulation, fiberboards and bio-fuel. Cannabis with a high THC concentration is known for its psychoactive effect, however, it is also studied for its essential medical properties. Although the immense majority of cannabis plants are considered hybrids, there is a general consensus which divides them into two big groups: Indica and Sativa. Indica plants are smaller and grow more densely,and their leaves are shorter and wider. They exert a soothing and relaxing effect. Sativa plants, by contrast, are taller and have less foliage, and their leaves are longer and slenderer. They generally produce a psychoactive and stimulating effect. Cannabis flowers produce innumerable chemical compounds. The three most important components that cause effects on the body are: cannabinoids, terpenes and flavonoids. One of the most widely studied cannabinoids is THC. It is responsible for the psychoactive effect, but can also act as an analgesic, muscle relaxant and relieve nausea. Most of the different cannabinoids do not produce intoxicating effects. The most well-known is Cannabidiol (CBD), a chemical compound that could offer multiple important therapeutic benefits, such as relieving nausea and seizures, like THC, but that also counteracts the intoxicating effects of this by reducing possible paranoia and anxiety. Cannabinoids predict a promising future in treatments against cancer and metastasis. But some also have very specific capacities, such as Cannabigerol (CBG),which promises to be a potent antibiotic very useful for treating skin diseases. Cannabidivarin (CBDV),is currently under investigation for the treatment of a type of epilepsy in which it may be more effective than CBD itself. And Tetrahydrocannabivarin (THCV), can reduce problems associated with obesity and diabetes, including nerve pain. The study of cannabinoids continues to grow and grow, let us not forget that there are more than 100 cannabinoids identified. Further research will help us to understand better the innumerable properties of cannabis.