Marijuana (cannabis) primarily comes from the cannabis plant (cannabis sativa). The cannabis plant is also used to produce hashish (hash) and hash oil. Of the three, marijuana (cannabis) is the most common but all forms of the drug are capable of causing a variety of physical and mental problems resulting from intoxication and long-term use.
Marijuana (cannabis) is known by a variety of other names, including: pot, grass, weed, ya(r)ndi, rope, mull, dope, skunk, bhang, ganja, hash, chronic, reefer, joint, cone or spliff.
http://www.drugs.health.gov.au/internet/drugs/publishing.nsf/content/marijuana2