Drug of abuse tests, also known as drug tests, are used to detect the presence of illegal or prescription drugs in a person's system. This type of testing is commonly used in workplaces, schools, and by law enforcement agencies. The tests can be conducted using various methods, including urine, blood, hair, and saliva samples.

There are various types of drugs that are classified as illegal or illicit substances, commonly known as drugs of abuse​. These drugs have different chemical compositions and effects on users. Some of the most commonly used drugs of abuse include opioids, cocaine, cannabis, amphetamines, hallucinogens, and designer drugs.

World Drug Day, also known as International Day Against Drug Abuse and Illicit Trafficking, is observed every year on June 26. It is a United Nations designated day to raise awareness about the dangers of drug abuse and illicit trafficking of drugs.