Why diversification matters
Owning many holdings reduces the damage if one company or sector struggles. A single share can go to zero; a broad global fund is unlikely to — though it can still fall sharply in a market downturn.
Simple ways to diversify
Low-cost index funds and ETFs are a common way to hold hundreds or thousands of companies in one line. Compare options on [funds & ETFs](/invest/funds-and-etfs) and keep an eye on ongoing charges.
Diversification does not remove market risk. It mainly reduces concentration risk.