### Comment:
An index fund is just a fund that tracks an index, it can be a mutual fund or an ETF. Like, SPY is one of many index ETFs that track the S&amp;P 500; Vanguard's equivalent is VOO.

### REPLY:
True, but SPY has waaaay lower fees than a mutual fund doing the same thing right? If I'm not mistaken...thats why I wonder why anyone would get the mutual fund versions. Is vanguard VOO an ETF style too though?

### END.