Crack cocaine can be thought of as just another form of cocaine. It became popular for many of the same reasons cocaine became popular, i.e. the stimulating effect, moderate risk of overdose, and availability. The reason it came to be so popular in the 1980's has to do with the difference between crack cocaine and powder cocaine. Crack is cheap, while powder is expensive. Powder cocaine became popular in the 1970's amongst middle-class whites in the US, but it was very expensive. Drug dealers in poorer areas wanted a way to sell a product that people would want, but could not afford. The solution was to make crack cocaine by mixing powder cocaine and baking soda (sodium bicarbonate). In this you could provide small doses of smokeable cocaine that were quite cheap per dose. The effect of smoking it made the high more intense as the drug entered the system quicker than through the nasal passages, but also subsided quicker. So here you have a powerful drug, sold cheaply. It was a recipe for success. The problem came not necessarily from the pharmacological effects of the drug, but from the battle over distribution waged by various gangs. This led to the introduction of draconian mandatory minimums for crack after basketball star Len Bias died while reportedly using the drug (though I believe the toxicology screen only identified cocaine in his system, and was unable to identify if it was crack or powder cocaine). The great Crack in America by Craig Reinarman will help cover anything I've missed in this response.