When the subject of drug use is addressed, most individuals think about the abuse of narcotics - yet the topic of drug use spans a whole plethora of different categories, including legal and illegal consumption of substances. History has shown that drug use has been a prominent part of human culture for thousands of years, so it is of a great deal of importance that this topic is studied. As time has gone on and humans have evolved, so have the substances used, especially during the past century, within which technology and the ability to produce different drugs has ameliorated greatly. This change has shown us many different trends of drug use throughout the past few decades, from the fluctuating popularity of illegal marijuana use to the use of controlled substances like alcohol or tobacco. The population of drug users includes a wide variety of different peoples as well, one can see the use of drugs spans across a spectrum of people of various backgrounds. Other aspects relating to the frequency of drug use by individuals can also demonstrate how diverse the population of drug users is, as well as it brings up the issue of differentiating between using, abusing, and being dependent on drugs. .
Throughout the history of the human race, drug use has been a prevalent factor in cultures; from early civilizations using different plant-derived psychoactive drugs for rituals to the use of alcohol and tobacco in other early cultures. Evidence from ancient Egypt and the Middle East show references to a liquid that was made in roughly the same process as beer. Opium use was popular for centuries in Asia, and was part of the reason that the "Silk Road" was born. South American countries have been practicing with Ayahuasca as part of spiritual experiences since before the Spanish landed in the area, and certain Native American tribes have been using mescaline, commonly known as peyote, for just as long.