There are a total of five types of drug testing, which are blood, urine, sweat, hair, and saliva. Drug testing can be done at a clinic or at home. It is required for when you want to apply for a job. Positive results can give you a lesser chance of getting hired but there are ways to make sure that you receive negative results. Or sometimes drug tests are just simply done when a parent wants to know whether or not their teenager is taking or doing drugs, but there are chances of receiving false positives.