NS&I Premium bonds are a tax-free and a 100% secure investment, however, the return is a lottery.

Basically, you can you put anywhere from £100 to £50,000 into a premium bond and it acts as a savings pot, so at any point, you could win up to £1 million (tax-free), but you could also have your money in there for a lifetime and never win a penny.

To find out more about the stock market, and what exactly it is click here.