Bursting the Bubble Tulips were the first, but they won’t be the last. What forms a “bubble” and what causes them to burst? Share | Related Content Should I Invest in Gold? Learning more about gold and its history may help you decide whether it has a place in your portfolio. Mutual Funds vs. ETFs Exchange-traded funds have some things in common with mutual funds, but there are differences, too. 5 Smart Investing Strategies Getting what you want out of your money may require the right game plan.