There are a number of risky behaviors - people who have disregard for danger and risk might get involved in any of the following:
- Criminal activity.
- Drug smuggling.
- Getting into fights.
- Taking drugs.
- Doing stunts in a car or motorbike. Also drag racing and street racing.
Unfortunately, I know people who I went to school with who have engaged in some of the above risky behaviors, and even though they have sort of calmed down as they became older and more mature, there are people of all ages that are guilty of doing these things.
Some of them involve risk for others too, like getting involved in crimes like robbery, while other risky behaviors can pose a danger only to oneself.