For as little as $1, this low-cost ETF gives investors exposure to thousands of companies.

Some of the largest index funds and exchange-traded funds (ETFs) in the world track the S&P 500 . The Vanguard S&P 500 ETF ( VOO 0.01% ) has a staggering $1.37 trillion in net assets. Other popular ETFs, like the SPDR S&P 500 ETF and the iShares Core S&P 500 ETF , each have over $650 billion in net assets. The Invesco QQQ Trust , which mirrors the performance of the Nasdaq-100 , has over $365 billion in net assets.

As large as these popular funds are, they are no match for the Vanguard Total Stock Market ETF ( VTI 0.06% ) -- which just surpassed $2 trillion in net assets. Here's what separates this ETF from S&P 500 index funds and why it's a top buy for long-term investo

See Full Page