You'll want to have a mix of different asset classes in your portfolio to balance the potential for growth and the risk that you'll lose money. (northwesternmutual.com)
It's the relative amounts of different asset classes in your portfolio which will determine how much risk your portfolio has. (abcsofinvesting.net)
To add balance as an investor means to invest in different asset classes that have an inverse relationship. (thefinancialjourneyman.com)