When you think of investing in stocks, you probably think of considering each company one by one, researching that particular player -- and then buying if the investment case looks solid. You can do this by getting in on a good exchange-traded fund (ETF),

A seemingly unstoppable flood of money has Vanguard Group Inc. on the brink of claiming a crown that State Street Corp. has held for decades.

The energy sector may not benefit as much from prevailing market themes like artificial intelligence, robotics, or cloud computing, but it does include a variety of quality dividend stocks with inexpensive valuations.

Here are my three favorite Vanguard ETFs to buy and hold for decades. Warren Buffett doesn't give a seal of approval to ETFs like Good Housekeeping does with consumer products. If he did, though, I suspect the Vanguard S&P 500 ETF (NYSEMKT: VOO) would be the first to receive such a distinction from the legendary investor.