Drug subcultures are groups of people united by a common understanding of the meaning and value (good or otherwise) of the incorporation into life of the drug in question. Such unity can take many forms, from friends who take the drug together, possibly obeying certain rules of etiquette, to full-scale political movements for the reform of drug laws. The sum of these parts can be considered an individual drug's "culture".

There are multiple drug subcultures based on the use of different drugs - the culture surrounding cannabis, for example, is very different from that of heroin, due to the different sort of experiences, sentiment amongst the crowd attracted to the drug in question, as well as the problems the users encounter.

Drugs also play an important role in various other subcultures, such as reggae music, Rastafari, hippie movements, drug dealing, as well as rave culture. Many artists, especially in 19th century and since then, used various drugs and explored their influence on human life in general and particularly on the creative process. Hunter S. Thompson's Fear and Loathing in Las Vegas employs drug use as a major theme and provides a critique of the drug culture of the 1960s.

4:20 or 4/20 (pronounced four-twenty) refers to consumption of cannabis and, by extension, a way to identify oneself with cannabis drug subculture.

The origin of the term stems from a story about a group of teenagers at San Rafael High School in San Rafael, California, United States in 1971. The teens would meet after school at 4:20 p.m. to smoke marijuana at the Louis Pasteur statue.

According to an April 2009 article on the Huffington Post, the group called itself the Waldos because its members hung out by a wall after school. Writer Ryan Grim, citing interviews with anonymous Waldos, claims that the group met by the statue at 4:20 p.m. to begin a search for a crop of unguarded cannabis growing near Point Reyes that they had heard about. They never found the stash, Grim writes, but smoked plenty of marijuana while looking for it.

April 20 ("4/20" in U.S. date notation) has evolved into a counterculture holiday, where people gather to celebrate and consume cannabis. In some locations this celebration coincides with Earth Week.

Stoner rock and stoner metal are interchangeable terms describing sub-genres of rock and heavy metal music. It combines elements of psychedelic rock, blues-rock and doom metal. Stoner rock is typically slow-to-mid tempo and features low-tuned guitars, a bass-heavy sound,melodic vocals, and 'retro' production. The genre emerged during the early 1990s and was pioneered foremost by the Californian bands Kyuss and Sleep.

The progenitors of stoner rock, like their followers today, often share the characteristic that they and their audience are recreational users of cannabis, or "stoners". While it would be grossly inaccurate to describe all fans and performers of stoner rock as marijuana users, it is certainly accepted that the effects of marijuana and the downtuned, slow, and psychedelic riffs of stoner rock complement one another — which eventually led to the common usage of the term "stoner rock" or "stoner metal" to define the genre.

This kind of connection between music and the use of drugs is not unique in music culture. Similar comparisons can be made between dance music and recreational drugs such as ecstasy. Various musicians who identify themselves as marijuana users (notably Pantera, who have included cannabis logos on their merchandise) do not qualify as "stoner rock" as the style of their musical output is largely outside the genre.

Stoners typically dress in normal (or sometimes grunge) clothing, with drug-related imagery/motifs.

Info -save for that little mini-paragraph on the end there- from wikipedia, image from deviantart.