As the world's most commonly-used illegal drug, it's not surprising that cannabis attracts its fair share of controversy, praise and vitriol. Its supporters insist it's a safe recreational drug and far less harmful than alcohol or tobacco. Its detractors insist it leads to psychological problems, addiction and that it's a gateway drug - one that leads the user on the path to more harmful drugs. Here's a look at this colourful and legendary drug.

First, let's define exactly what we mean by cannabis. There are various definitions but essentially both cannabis and marijuana refer to the leaves, flowers and buds of the cannabis plant whether cannabis sativa, cannabis indica and cannabis ruderalis. Marijuana is mainly used as a recreational drug producing feelings of euphoria when smoked or eaten. Its popularity and long history is evident from the fact that there are over 200 slang terms for marijuana including "pot," "herb," "weed," and "boom."

The roots, stalk, and stems of the cannabis plant are known as hemp. Hemp has a long tradition of use for the production of paper, textiles, oil, rope and clothing among many others. This distinction is important because it impacts the illegality of the plant. Marijuana is generally illegal in most countries while hemp is not.

Use of the cannabis plant dates back to 6000 B.C. when hemp seeds were eaten for sustenance in China. Later in the same country came the first written records of the use of cannabis for medical purposes. It was documented as a medication to treat a whole range of complaints including rheumatism, gout, and malaria.

It became popular for its psychoactive properties in Muslim countries in the Middle and Near East where alcohol was forbidden and from there spread to Europe and America.

Meanwhile marijuana was prized by Hindu mystics in the subcontinent who used it to help reach higher planes of consciousness. It was one of the five sacred plants of India, used as a medicine, and as an offering to the god Shiva. Even today, the saddhus of India and Nepal still use cannabis to further their spiritual development.

As for Western countries, marijuana was one of the main medicines in the United States for most of the 19th century being used to treat conditions ranging from headaches to nausea. It was also sold as a nerve tonic. However, in 1928, the recreational use of marijuana was banned in Britain and in the United States in 1937.

Marijuana re-entered the public consciousness in Western countries during the 1950s when it was taken up by the beat generation. It became even better known during the 1960s when it became the central part of the hippy pharmacopeia.

In recent years, authorities have come to realize the potential of marijuana as a therapeutic agent for many serious medical conditions. Marijuana contains over 60 chemicals with medical uses.

Canada became the first country to legalize medical marijuana in 2003. In the United States, laws are on a state by state basis with Alaska, California, Colorado, Hawaii, Maine, Maryland, Michigan, Montana, Nevada, New Mexico, Oregon, Rhode Island, Vermont and Washington now having medical marijuana laws. The list of diseases which cannabis can be used for includes: multiple sclerosis, cancer, HIV/AIDS, glaucoma, depression, epilepsy, migraine and asthma.

Other uses for marijuana include luxury bird food. In many countries including Belgium, for example, it is legal to produce and sell pot seeds on the condition that they are only used to feed birds.

The jury is still out on the pernicious effects of marijuana on the brain and other parts of the body. Hundreds of studies have proved that it is harmful and hundreds of others have proved that it's not. This is not to say that cannabis use is without danger. Excessive or prolonged use of any substance can lead to all kinds of problems and with a plant with psychoactive properties, one should be especially careful. At the end of the day, it's up to the individual to consider the evidence and decide what he believes.

Meanwhile though cannabis is still illegal in the UK, it is lawful to buy and own the seeds providing they're not germinated. If you want to add sensi seeds to your collection of souvenirs or for use as fish bait, you can visit one of the many online vendors of pot seeds and your order will be delivered through the post.