Indica originates from the Hindu Kush Mountains of Central Asia and is known for its relaxing and more sedating effects on the user. Sativa has a more active, cerebral and uplifting effect, while a hybrid combines the two.
Beyond indica, sativa, and hybrid, the types of cannabis can also be classified into strains. Strains are fundamentally different breeds of cannabis, and they’re bred to have specific effects on the user.
Not all seeds sold under the same name are genetically identical or even necessarily related. Some producers may choose to create a strain name as a branding exercise or identify their product with an existing name because they believe the product matches characteristics the market expects from the product sold under that name.
If you purchase a product from a quality source, the strains should be more or less consistent. However, to gain more control over strain characteristics, many consumers are now cultivating their weed where it's legal.