In financial investments, the signs of the times currently consist of three letters: ETF. Globally, $9.8 trillion was recently invested in exchange-traded index funds.

But few investors know exactly how ETFs work. At first glance, the differences between the individual offers do not appear to be very large. But it is worth paying attention to the details. Because funds that map the same index can differ significantly in their structure. Depending on the construction, this can have an impact on the return, which adds up to large amounts over longer periods of time.