In the following video, Fool contributor Matt Thalman discusses why Apple (NASDAQ:AAPL) and Microsoft (NASDAQ:MSFT) became the world's largest companies and why (NASDAQ:AMZN) may one day also hold that title.

Matt also explains why investors shouldn't be focusing their time on figuring out what may become the next largest company in the world. Instead, he says, they should spend their time looking for the best companies in different industries, and then everything else will take care of itself.

Fool contributor Matt Thalman owns shares of Apple, Microsoft, and The Motley Fool recommends and Apple and owns shares of, Apple, and Microsoft. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.