Hemp (from Old English hænep) is a term reserved mainly for low tetrahydrocannabinol (THC) strains of the plant Cannabis sativa. Of the approximately 2000 cannabis plants varieties known, about 90% contain only low-grade THC and are most useful for their fiber, seeds and medicinal or psychoactive oils. Scholars believe that hemp is humankind's oldest cloth and hemp-limestone composites have been found in ancient Roman architecture.

In modern times hemp is used for industrial purposes including paper, textiles, clothing, biodegradable plastics, construction (as with Hemcrete and insulation), body products, health food and bio-fuel. Hemp is thus legally grown in many countries across the world including Spain, China, Japan, Korea, England, France, Africa, North Africa, Egypt and Ireland. Although hemp is commonly associated with marijuana (hemp's THC rich cousin), since 2007 the commercial success of hemp food products has grown considerably.

Hemp is one of the faster growing biomasses known, producing up to 25 tonnes of dry matter per hectare per year. A typical average yield in large scale modern agriculture is about 2.5–3.5 t/ac (air dry stem yields of dry, retted stalks per acre at 12% moisture). Approximately one tonne of bast fiber and 2–3 tonnes of core material can be decorticated from 3–4 tonnes of good quality, dry retted straw.

Jack Herer (June 18, 1939 – April 15, 2010), sometimes called the "Emperor of Hemp", was an American cannabis activist and the author of The Emperor Wears No Clothes, a book which has been used in efforts to decriminalize cannabis. Herer also founded and served as the director of the organization Help End Marijuana Prohibition (HEMP).

A former Goldwater Republican, Herer was a pro-cannabis (marijuana) and hemp activist. He wrote two books, the aforementioned The Emperor Wears No Clothes and Grass. There has also been a documentary made about his life called, The Emperor of Hemp (cite?).

He believed that the cannabis plant should be decriminalized because it has been shown to be a renewable source of fuel, food, and medicine that can be grown in virtually any part of the world. He further asserts that the U.S. government deliberately hides the proof of this.

A specific strain of cannabis has been named after Jack Herer in honor of his work. This strain has won several awards, including the 7th High Times Cannabis Cup. Jack Herer was also inducted into the Counterculture Hall of Fame at the 16th Cannabis Cup in recognition of his first book.

Rick Simpson is an American set decorator. He won an Academy Award and was nominated for another in the category Best Art Direction.

Simpson won an Academy Award for Best Art Direction and was nominated for another: