Every investment sits somewhere on a spectrum between low risk/low potential reward and high risk/high potential reward — and there is no way to get high returns with zero risk, no matter what anyone claims. A savings account or government bond offers modest, fairly predictable returns with very little chance of losing your principal. A single small-company stock offers the chance of dramatic gains, but also the real chance of a dramatic loss.
"Risk" in investing doesn't just mean "chance of losing money" — it more precisely means uncertainty and variability of outcome. A highly volatile stock can swing wildly in both directions; a bond generally moves in a much narrower, more predictable range. Two investments can have the exact same AVERAGE expected return over time while having very different risk — one arriving there smoothly, the other via a rollercoaster of ups and downs.
The right amount of risk to take on is genuinely personal — it depends on your time horizon (money needed next year should generally sit somewhere much steadier than money you won't touch for 30 years), your goals, and your own tolerance for watching your account value swing around. This is exactly why financial advice is rarely one-size-fits-all: the same stock can be a reasonable choice for one person's portfolio and a poor fit for another's, purely based on when they need the money and how they'd react to a big paper loss.
Correct moves you up, wrong moves you down — reach 100 to master this lesson.