"RISK can be defined as “the threat or probability that an action or event will adversely or beneficially affect an organisation's ability to achieve its objectives”. In simple terms risk is ‘Uncertainty of Outcome’, either from pursuing a future positive opportunity, or an existing negative threat in trying to achieve a current objective."
That's a pretty good technical description of risk. Basically, a risk is something that will go wrong at the worst possible moment causing untold grief, angst and turmoil.
If you're asking about Mom or Dad telling you not to take risks, then they're probably talking about some threat or possibility of a threat to harm, dismemberment, injury, or other bad outcome to something you're consider doing. A good risk management practice would be to listen to Mom and Dad.
If you're talking about risk in the business world; risk is inherent in every thing we do. Economists talk about opportunity cost. That's a form of risk. If you do one thing, then you give up the opportunity of doing something else. You analyze the risks associated with what you want to do, versus what you could do other wise, and hopefully make the best decision for your circumstance.
We take risks every day. We get in the car and drive to work or school. We risk our life on the highway with the expectation that the payoff will be worth it (i.e. getting to where we're going because the opportunity cost of not being their is too high not to go). We manage that risk by driving safely, wearing seatbelts, signaling lane changes, looking in the rear view mirror, and things like that.
Anyone who'll tell you that this is a "Risk Free" anything; hasn't carefully considered what the actual risks are. Nothing in life is risk free. Granted, the probability or likelihood of the risk happening may be low, but if it does happen, the outcome will not always be pleasant. When making decisions about risks, in your personal or business life, you need to analyze the outcomes and decide if you can accept it or not. If you can't accept the outcome of the risk, then you need a well thought out plan to do something different.